• Korean Journal of Optics and Photonics
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• v.7 no.4
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• pp.375-385
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• 1996

Recently interest in the fabrication of LD operated by low current is gradually increasing as fabrication techniques of MQW-LD are progressed. In this viewpoint, theoretical estimation for decreasing the amount of threshold current will be helpful to design and make LD in case that active layer of conventional bulk type RWG-LD structure is replaced with MQW structure. Therefore, the optimum design condition of RWG MQW-LD was obtained from theoretical analysis in order to operate in the weakly index-guided LD and low threshold current. The lateral effective index step has been obtained in RWG MQW-LD structure. Waveguide mechanism including this index step has been investigated by solving the carrier diffusion equation and lateral wave equation. From these theoretical results, the optimum design condition of RWG MQW-LD have been suggested.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.481-485
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• 2002

In this study, we fabricated the PBH-LD by meltback method using the LPE. The PBH-LDs are analyzed the leakage current that flows through leakage current path like the p-n diode and p-n-p-n current blocking layer. We observed the variation of threshold current with the leakage width $W_{ι}$. As a consequence, we confirmed that the threshold current became low in the decrease of the leakage width and in the increase of the ratio of specific resistivity of leakage region to active region. We also compared between the calculated threshold current in the absence of leakage region and the measured threshold current in the device. As a result, the ratio of specific resistivity was about 0.5 in the measured LDs, which have the width of a active layer of 1.4${\mu}{\textrm}{m}$ and leakage width of 0.6${\mu}{\textrm}{m}$.

• Korean Journal of Optics and Photonics
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• v.7 no.2
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• pp.150-156
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• 1996

RWG MQW-LD has been made with our vertical LPE system from the optimal design condition for the RWG MQW-LD to be activated as weakly index-guided LD. Through several experiments we have established the growth condition which can be used through to grow the MQW-DH wafer and to control the thickness of MQW layer to ~200$\AA$. 4 ${\mu}{\textrm}{m}$-thickness of the ridge pattern has been formed through the photolithographic process on the MQW-DH wafer grown by the former condition, and then we have fabricated the RWG MQW-LD using it. From the result of measuring the electro-optical characteristics we can make sure that it can be lasing as lasing as laterally single mode at even more than $2.7I_{th}$.

• Journal of Yeungnam Medical Science
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• v.3 no.1
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• pp.193-199
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• 1986

Body fluid Lactate dehydrogenase and its isoenzyme measurement was performed in 132 patients: 8 cases with peritonitis, 21 cases with malignant ascites, 43 cases with liver cirrhosis, 48 cases with tuberculous pleuritis, 12 cases with malignant pleural effusion respectively. Body fluid protein and glucose contents, red blood cell counts, white blood cell counts, cytologic examination were also performed as a comparative study. The results were as follows: 1. Measurement of total LD and protein amount could differentiate between transudate and exudate in the ascitic fluids. 2. In the malignant exudate of ascites and pleural fluid, the activity of LD2 isoenzyme was statistically increased compared with that of inflammatory exudate and the activity of LD4 isoenzyme was also increased compared with that of serum(P<0.05). 3. The inflammatory exudate of pleural fluid and ascites demonstrated the increase of LD5 isoenzyme activity stastistically compared with that of serum and malignant exudate(P<0.05). 4. A difference of total LD activity between malignant ascites and inflammatory ascites was significant statistically, while this was not observed in the pleural exudate. 5. Total LD and LD5 isoenzyme activity didn't correlated with the number of white blood cells in the exudate.

• ETRI Journal
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• v.4 no.1
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• pp.3-8
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• 1982

성장된 GaInAsP/InP DH wafer로부터 상온에서 duty 5%까지 Pulse 동작이 가능한 전면전극(broad contact) 및 stripe 구조 LD(711이저 다이오드)를 제작하였다. 또 이렇게 제작된 LD의 I-V특성, 1-L 특성 및 발진파장 등을 조사하기 위해 LD 구동회로 및 Ge 태양전지와 Ge-APD를 이용한 광 검출회로를 제작하였다. 이들을 이용해 제작한 LD의 특성을 조사한 결과 stripe 구조 LD인 경우 발진개시전류($I_th$)가 900mA, 발진파장이 $1.29\mum$, 파장반치폭(FWHM)이 $60\AA$였으며 $1.33I_th$까지 kink 없이 동작이 가능하였다.

• Journal of Korean Neurosurgical Society
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• v.57 no.3
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• pp.167-173
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• 2015

Objective : Removal of blood from subarachnoid space with a lumbar drainage (LD) may decrease development of cerebral vasospasm. We evaluated the effectiveness of a LD for a clinical vasospasm and outcomes after clipping of aneurysmal subarachnoid hemorrhage (SAH). Methods : Between July 2008 and July 2013, 234 patients were included in this study. The LD group consisted of 126 patients, 108 patients in the non LD group. We investigated outcomes as follow : 1) clinical vasospasm, 2) angioplasty, 3) cerebral infarction, 4) Glasgow outcome scale (GOS) score at discharge, 5) GOS score at 6-month follow-up, and 6) mortality. Results : Clinical vasospasm occurred in 19% of the LD group and 42% of the non LD group (p<0.001). Angioplasty was performed in 17% of the LD group and 38% of the non LD group (p=0.001). Cerebral infarctions were detected in 29% and 54% of each group respectively (p<0.001). The proportion of GOS score 5 at 6 month follow-up in the LD group was 69%, and it was 58% in the non LD group (p=0.001). Mortality rate showed 5% and 10% in each group respectively. But, there was no difference in shunt between the two groups. Conclusion : LD after aneurysmal SAH shows marked reduction of clinical vasospasm and need for angioplasty. With this technique we have shown favorable GOS score at 6 month follow-up.

• Food Science of Animal Resources
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• v.41 no.2
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• pp.343-352
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• 2021

The objective of this study was to evaluate the effects of Lactobacillus acidophilus ATCC 43121 and L. fermentum MF27 on biochemical indices in the serum, cholesterol metabolism in the liver and mucin expression in the gallbladder in lithogenic diet (LD)-induced C57BL/6J mice to determine the preventive effects of lactobacilli on gallstone formation. By the end of 4 wk of the experimental period, mice fed on a LD with high-fat and high-cholesterol exhibited higher levels of total and low-density lipoprotein cholesterol in the serum compared to mice fed on control diet or LD with L. acidophilus ATCC 43121 (LD+P1; p<0.05). Cholesterol-lowering effects observed in the LD+P1 and LD with L. fermentum MF27 (LD+P2) groups were associated with reduced expression of 3-hydroxy-3-methylglutaryl coenzyme A reductase in the liver compared to the LD group (p<0.05). Furthermore, expression of the gel-forming mucin, including MUC5AB and MUC5B, was suppressed in the LD+P1 and LD+P2 groups compared to the LD group (p<0.05). Therefore, steady intake of both L. acidophilus ATCC 43121 and L. fermentum MF27 may have the ability to prevent the formation of cholesterol gallstones in LD-induced C57BL/6J mice.

• Korean Journal of Optics and Photonics
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• v.3 no.4
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• pp.252-257
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• 1992

In this study, InGaAsP/InP MQW-DH wafer was grown by a vertical type LPE system and 10$\mu$m stripe MQW-LD was fabricated with the wafer. The threshold current was about 200 mA and when the cavity length of the LD was 470$\mu$m the central wavelenth of gain spectra was 1.32$\mu$m the lasing wavelength was 1.302$\mu$m which corresponded to the gain center of the quantum well thickness of 300 $\AA$.

• Korean Journal of Human Ecology
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• v.23 no.6
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• pp.1217-1229
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• 2014

The purpose of this study was to investigate the quality characteristics and antioxidative effect of Dasik prepared with Lycii fructus extract(LD). LD were added in ratios (w/w) of 0(C), 5(LD1), 10(LD2), and 15%(LD3), and then proximate compositions, physicochemical properties, sensory evaluations and antioxidative effect of the Dasik were measured. LD1~LD3 samples showed higher contents of moisture, crude lipid, crude protein and crude ash as well as pH and sugar content compared to control (p<0.001). The total phenol content of LD samples (LD1, 31.5% ; LD2, 66.1% ; and LD3, 69.7%) was higher than that of control (4.71%). DPPH radical scavenging activity of LD3 showed the highest activity of 65.3%, whereas that of control (27.0%) was the lowest among samples. Additionally, ABTS radical scavenging activity of LD samples was higher than that of control (C, 38.9% ; LD1, 53.6%; LD2, 80.5% ; and LD3, 83.3%). The results of texture analysis on all samples showed that control had the highest but LD3 was the lowest (p<0.001). In sensory evaluation, the scores of appearance, flavor, taste and overall preference for LD2 was significantly higher than the samples(C, LD1, and LD2). Form the findings, this study suggests that 10% addition of LD was effective for preparation of Dasik in the aspects of the consumer acceptability and functionality.

• Journal of the Institute of Convergence Signal Processing
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• v.21 no.4
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• pp.162-169
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• 2020

In this paper, we attempted a qualitative understanding of mutual injection locking without rigorous mathematics, and analyzed the proposed mutual injection locked light source. Also, a low-cost WDM-PON light source based on mutual injection locking using two unpolarized Fabry-Perot Laser Diodes (F-P LDs), was implemented. The RIN (Relative Intensity Noise) characteristic for the wavelength change of the F-P LD was measured, and when the variable wavelength range was 2.07 nm, it showed a RIN of at least -110 dB/Hz.