• The Korean Journal of Physiology and Pharmacology
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• v.7 no.6
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• pp.295-301
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• 2003

Striatum plays a crucial role in the movement control and habitual learning. It receives an information from wide area of cerebral cortex as well as an extensive serotonergic (5-hydroxytryptamine, 5-HT) input from raphe nuclei. In the present study, the effects of 5-HT to modulate synaptic transmission were studied in the rat corticostriatal brain slice using in vitro extracellular recording technique. Synaptic responses were evoked by stimulation of cortical glutamatergic inputs on the corpus callosum and recorded in the dorsal striatum. 5-HT reversibly inhibited coticostriatal glutamatergic synaptic transmission in a dose-dependent fashion (5, 10, 50, and $10{\mu}M$), maximally reducing in the corticostriatal population spike (PS) amplitude to $40.1{\pm}5.0$% at a concentration of $50{\mu}M$ 5-HT. PSs mediated by non-NMDA glutamate receptors, which were isolated by bath application of the NMDA receptor antagonist, d,l-2-amino-5-phospohonovaleric acid (AP-V), were decreased by application of $50{\mu}M$ 5-HT. However, PSs mediated by NMDA receptors, that were activated by application of zero $Mg^{2+}$ aCSF, were not significantly affected by $50{\mu}M$ 5-HT. To test whether the corticostriatal synaptic inhibitions by 5-HT might involve a change in the probability of neurotransmitter release from presynaptic nerve terminals, we measured the paired-pulse ratio (PPR) evoked by 2 identical pulses (50 ms interpulse interval), and found that PPR was increased ($33.4{\pm}5.2$%) by 5-HT, reflecting decreased neurotransmitter releasing probability. These results suggest that 5-HT may decrease neurotransmitter release probability of glutamatergic corticostriatal synapse and may be able to selectively decrease non-NMDA glutamate receptor-mediated synaptic transmission.

• Journal of the Korea Society for Simulation
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• v.15 no.3
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• pp.87-91
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• 2006

With the growth of the internet, the number of wireless internet users has increased continuously up to date. However, mobile communications could not support high speed transmission rate with cheap communication fee and wireless LAN has problems in providing terminal mobility and wide area connectivity, respectively. So the WMAN standard has been newly designed to make up for these limits. The initial 802.16 specification effectively offers a solution for providing fixed users with high speed wireless communication but it does not offer terminal mobility. So the 802.16d and 802.16e have been developed as the next generation solution that can support various PHY layer (SC, SCa, OFDM, OFDMA) and offer the terminal mobility. In this paper, we propose an effective uplink scheduling algorithm for VoIP with using UGS, and we show that our proposed algorithm is superior in view of average delay and management of uplink bandwidth to conventional rtPS algorithm and the scheme in reference, with using NS-2 network simulator.

• Journal of Chest Surgery
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• v.10 no.1
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• pp.148-155
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• 1977

The clinical findings with cardioangiography and successful surgical treatment of a 10 year old girl with double-outlet right ventricle is reported at The Dept. of Thoracic and Cardiovascular Surgery, Korea University Hospital, College of Medicine. The patient has been suffered from intermittent cyanosis, palpitation, and exertional dyspnea since 1 year after NFSD, and a holosystolic ejection murmur of grade 4 at the left 3rd intercostal space with mild cyanosis of the lips was the only physical findings at the time of this admission. Cardiac catheterization revealed ventricular septal defect with left to right shunt of 43% and right to left shunt of 10.2%. On cardioangiography from the left ventricle revealed all of the left ventricular outflow shunted into the right ventricle through the large ventricular septal defect, and the aorta originated from the infundibular chamber of the right ventricle with left, anterior sided pulmonary artery. The atria, viscera, and ventricles were normally located, and right ventricular out-flow was narrowed with infundibular hypertrophy and pulmonary valvular stenosis. Surgical correction was accomplished by closure of the ventricular septal defect in such a way that left ventricular outflow was routed via a Teflon felt prosthetic tunnel to the aorta, and pulmonary valvulotomy with infundibulectomy Was done to pass Hegar`s dilator No. 15 for reconstruction of the right ventricular outflow tract. The patient tolerated complete repair and has continued to improve over a period of three months after operation with normal school life. Details of the disease and method of repair are presented with related references.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.2
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• pp.138-143
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• 2016

The objective of this study was to evaluate the effects of the application of vermicomposts on the growth parameters and ginsenoside content of ginseng roots. Food waste vermicompost (FW), cow manure vermicompost (CM), and paper sludge vermicompost (PS) were applied at 10 and $40t\;ha^{-1}$, respectively. One-year-old seedlings were transplanted and 4-year-old roots were harvested. Soil nitrate and phosphate concentrations were increased in the plots applied with FW and CM at $40t\;ha^{-1}$. Soil pH and exchangeable Ca concentrations were higher at FW $40t\;ha^{-1}$ than at CM $40t\;ha^{-1}$. Root yield increased when treated with FW $40t\;ha^{-1}$ in comparison to the yield for the control. The incidences of root rot disease and ginsenoside content were not significantly affected by the treatments. The results suggested that application of vermicompost might not show a relationship between root biomass and ginsenoside content. It further showed that proper use of vermicompost can promote root yield without a reduction in root quality or an increase in the incidence of root rot disease in reclaimed fields.

• Bulletin of the Korean Chemical Society
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• v.26 no.9
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• pp.1369-1380
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• 2005

The reaction of methyl radical with iodine molecule on an attractive potential energy surface is studied by classical trajectory procedures. The reaction occurs over a wide range of impact parameters with the majority of reactive events occurring in the backward rebound region on a subpicosecond scale. A small fraction of reactive events take place in the forward hemisphere on a longer time scale. The ensemble average of reaction times is 0.36 ps. The occurrence of reactive events is strongly favored when the incident radical and the target molecule align in the neighborhood of collinear geometry. Since the rotational velocity of I2 is slow, the preferential occurrence of reactive events at the collinear configuration of $CH_3{\ldots}I{\ldots}$I leads to the reaction exhibiting an anisotropic dependence on the orientation of $I_2$. During the collision, there is a rapid flow of energy from the $H_3C{\ldots}$I interaction to the I-I bond. The $CH_3I$ translation and $H_3C$-I vibration share nearly all the energy released in the reaction, and the distribution of the vibrational energy is statistical. The reaction probability is $\cong$0.4 at the $CH_3$ and I2 temperatures maintained at 1000 K and 300 K, respectively. The probability is weakly dependent on the $CH_3\;and\;I_2$ temperatures between 300 K and 1500 K.

• Journal of the Microelectronics and Packaging Society
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• v.16 no.4
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• pp.55-60
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• 2009

Porous silicon film is fabricated by electrochemical etching in a chemical mixture of HF and ethanol. Effects of Si type, Si resistivity, ultrasonic frequency, current density and etching time on surface morphology of PS film were studied. Electrochemical etching in ultrasonic bath promotes the uniformity of porous layer of Si. Frequency of ultrasonic was increased from 40 kHz to 130 kHz to obtain uniform pores on the Si surface. When current density was higher, the sizes of pores were larger. The new etching cell using back contact metal and current shield help to overcome nonhomogeneity and current crowding effect, and then leads to fabricate uniform pores on the Si surface. The distribution of pore size shows no notable tendency with etching time.

• JSTS:Journal of Semiconductor Technology and Science
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• v.6 no.3
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• pp.146-153
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• 2006

We have been investigating InGaAs HEMTs as a future high-speed and low-power logic technology for beyond CMOS applications. In this work, we have experimentally studied the role of the side-recess spacing $(L_{side})$ on the logic performance of 50 nm $In_{0.7}Ga_{0.3}As$ As HEMTs. We have found that $L_{side}$ has a large influence on the electrostatic integrity (or short channel effects), gate leakage current, gate-drain capacitance, and source and drain resistance of the device. For our device design, an optimum value of $L_{side}$ of 150 nm is found. 50 nm $In_{0.7}Ga_{0.3}As$ HEMTs with this value of $L_{side}$ exhibit $I_{ON}/I_{OFF}$ ratios in excess of $10^4$, subthreshold slopes smaller than 90 mV/dec, and logic gate delays of about 1.3 ps at a $V_{CC}$ of 0.5 V. In spite of the fact that these devices are not optimized for logic, these values are comparable to state-of-the-art MOSFETs with similar gate lengths. Our work confirms that in the landscape of alternatives for beyond CMOS technologies, InAs-rich InGaAs FETs hold considerable promise.

• The Korean Journal of Community Living Science
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• v.21 no.1
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• pp.117-124
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• 2010

Recently, research on variables associated with hair styles are increasing with the spreading of total coordinated intention in the fields of clothing and cosmetology. In the present study, we focused on examining the skin temperature on the scalp(the vertex, temporal, and occiput), humidity on the occiput, skin temperatures (the forehead, back of ear, back of neck, upper back, abdomen, forearm, hand, thigh, calf, and foot), rectal temperature, total body mass loss by hair styles in a thermal neutral environment. Four young females participated as subjects. For a certain period, each subject had the five different hair styles in a random order: (1)Straight short hair(SS), (2)Perm waved short hair(PS), (3) Straight long hair(SL), (4)Perm waved long hair(PL), (5)Ponytail style(PT). Subjects wore briefs, bra, shirts with long sleeves, long legged training pants, and socks. The environmental variables of a climatic chamber were kept constant at $21{\pm}0.5^{\circ}C$ of air temperature and 55${\pm}$5%RH of air humidity. The results indicated the following: The skin temperature and humidity on the scalp did not show any significant differences among five different hair styles, but straight long hair style(SL)was the highest on the vertex, temporal, and occiput. The temporal skin temperature($29.8\sim30.8^{\circ}C$) was the highest, while the vertex skin temperature($28.7\sim30.1^{\circ}C$) was the lowest. Humidity on the occiput was the highest in the perm waved long hair style(PL). The back of ear skin temperature was significantly lower in the ponytail style(PT) than in the other four hair styles(p<.001). In the straight long hair style(SL), the skin temperature on the back of the neck and on the upper back were significantly higher than those of the other four hair styles(p<.01). Mean skin temperature and rectal temperature had no significant differences among hair styles. Total body mass was the highest in the perm waved long hair style(PL)(p<.05). We acquired fundamental data to enable the improvement of the current hair clinic system, wigs, functional hats, and helmets.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.4
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• pp.1-8
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• 2004

A novol clock distribution scheme is proposed for high-speed and low-power digital system to minimize clock skew and reduce dynamic power consumption. This scheme has ideal zero-skew characteristic by using folded clock lines (FCL) and phase blending circuit. For analyzing suitable line structures to FCLs, microstrip line and coplanar line are placed with folded clock lines. Simulation results show that the maximum clock-skew between two receivers located 10mm apart is less than lops at 1㎓ and the maximum clock-skew between two receivers located 20mm apart is less than 60ps at 1㎓. Also the results show that the minimum skews of clock signals regardless of process, voltage, and temperature variation are invariant.

• Journal of Digital Convergence
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• v.16 no.2
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• pp.479-488
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• 2018

To develop and test validity and reliability of Korean version of the Student Perception of Patient Safety Knowledge, Skills, Attitudes to assess applicability for nursing students. Survey data were collected from convenience sample of 425 fourth year nursing students who enrolled in four universities. Data were evaluated using item analysis, content validity, exploratory factor analysis, and Cronbach's alpha. The attitudes scale was eliminated since item-total correlations were less than .3, on the final Korean Version Scales. The attitudes subscale needs further refinement before implementation. The finding out this study demonstrate that the knowledge and skills scales showed satisfactory validity and reliability. It is useful to evaluate nursing students during educational preparation and in practice.