• Journal of Korean Vacuum Science & Technology
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• v.2 no.1
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• pp.25-31
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• 1998

The reliability of fluorine doped silicon oxide (SiOF) films for intermetal dielectrics in multilevel interconnections of ultra-large scale integrated circuits (ULSIs) is investigated. SiOF films were deposited by electron cyclotron resonance plasma-enhanced chemical vapor deposition (ECRPECVD) using H-free source gases, i.e., SiF4 and O2. The effect of post plasma treatment on the moisture absorption and dielectric properties of SiOF films was carried out I terms of air exposure time, The reliability test of Cu/TiN/SiOF/Fi specimen was carried out in terms of temperature by rapid thermal annealing (RTA) in N2 ambient. After O2 plasma treatment,, no appreciable peak directly related to moisture absorption was detected. The capacitance-voltage (C-V) characteristics of the O2 plasma treated SiOF film showed that the film remained to hold the sound dielectric properties even after boiling treatment. The Cu/TiN/SiOF/Si system was found to be reliable up to $600^{\circ}C$.

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.2
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• pp.105-112
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• 2005

This study was conducted on paddy-land at Kimje, ChunBuk in Korea from Nov. 1999 to Nov. 2002. The aim of this study was to investigate the effect of pig slurry (PS) on dry matter (DM) yield, N yield and nutritive value of rye, and soil total nitrogen (TN), Phosphorus (P) and organic matter (OM) content. This experiment was consisted of 4 plot (chemical fertilizer; N: 100/100, $P_2O_5: 150,\;K_2O: 150$ kg/ha; PS $100\%$ treatment, PS $200\%$ treatment and PS $100\%$ treatment with half of CF). 1. DM yields of rye revealed that there was an increase in order; PS $100\%$ treatment with half of chemical fertilizer (CF) > PS $200\%$ treatment > full of CF treatment > PS $100\%$ treatment. 2. Crude protein (CP) content was the highest with PS $200\%$ treatment ($10.53\%$) and followed by PS $100\%$ treatment with half of CF and full of CF treatment and the lowest with PS $100\%$ treatment. 3. The contents of NDF and TDN were hardly influenced by PS and CF 4. N yields of rye revealed that there was an increase in order; PS $200\%$ treatment > PS $100\%$ treatment with half of CF > full of CF treatment > PS $100\%$ treatment. 5. The contents of TN and OM were not influenced by the application levels of PS. however, The TN content increased by the application of PS, as increasing the application period 6. P content of the soil was not affected by the application levels of PS during the experimental period.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.12-13
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• 2006

$Ga_2O_3$ is associated with the fabrication of thin window layer of solar cell. Usually, $Ga_2O_3$ is synthesized from Ga-metal oxidation method and GaN mono-crystal heat treatment method. We synthesized $Ga_2O_3$ powder using two methods and analyzed powder using latter method compared with powder by former method. XPS, XRD, IR analysis are conducted. XPS result, surface of GaN powder is almost oxidized to $Ga_2O_3$ at $1124^{\circ}C$ heat treatment and XRD and IR result, the inside of GaN powder is dramatically oxidized at $1124^{\circ}C{\sim}1300^{\circ}C$.

• Journal of the Korean Society for Heat Treatment
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• v.2 no.4
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• pp.1-10
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• 1989

To investigate the influence of temperature on the TiN film, it was deposited on the STC-3 steel and Si-wafer from $TiCl_4/N_2/H_2$ gas mixture by using the radio frequency plasma assisted chemical vapor deposition. The deposition was performed at temperature of $400^{\circ}C-500^{\circ}C$. The results showed that crystalline TiN film was deposited over $480^{\circ}C$, and all specimens showed the crystalline TiN X-ray diffraction peaks after vacuum heat treatment for 3 hrs, at $1000^{\circ}C$, $10^{-5}torr$. While the film thickness was increased above $480^{\circ}C$, it was decreased under $480^{\circ}C$ as temperature increased. And the contents of titanium were increased and it of chlorine were decreased as temperature increased. Because temperature increase was attributed to the increase in the density of TiN film, surface hardness of TiN film was increased with temperature.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.395-395
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• 2013

GaN는 LED, 태양전지, 그리고 전자소자 등에 쓰이는 물질로, 관련 연구가 활발히 진행되고 있으며, 이와 더불어 top-down방식을 활용한 소자제작 방법 또한 발달되고 있다. 하지만, 일반적으로 LED 제작에 사용되는 c-plane GaN의 경우, c축 방향으로 발생하는 분극의 영향을 받게되며, 분극은 LED내 양자우물의 밴드를 기울게 하여 전자와 홀의 재결합률을 감소시켜 낮은 내부양자효율을 야기한다. 이러한 문제를 해결하기 위해 여러 가지 방법들이 제시되었으며, 그 중에서도 a면, 혹은 m면과 같은 nonpolar면을 사용하는 GaN LED가 주목받고 있다. 본 연구에서는, top-down방식을 통해 약 $2{\mu}m$ 크기의 diameter를 갖는 micro-sized column LED를 구현하였으며, 식각 후 드러나는 semipolar면을 wet treatment를 통해 제거하여 nonpolar면을 드러나게 하였으며, 이 면에 Ni/Au를 contact하여, 전기적, 광학적 특성을 논하였다. Fig. 1은 I-V 특성 그래프이며, Fig. 2는 EL측정 결과(광학적 특성)이다.

• Korean Journal of Schizophrenia Research
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• v.24 no.2
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• pp.60-67
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• 2021

Objectives: The optimal duration of maintenance treatment for patients with first-episode schizophrenia (FES) remains unclear. We examined the first antipsychotic treatment duration and its association with re-initiation of treatment using a nationwide claim database. Methods: Data from the Health Insurance Review and Assessment Service database in South Korea for 2007-2016 were used. Linear regression analysis and Cox proportional hazard models were used to evaluate the associations between the duration of the first antipsychotic treatment, time to re-initiation of treatment, and occurrence of treatment re-initiation. Results: Of 30,143 patients with FES, 80.4% (n=24,231) received <2 years of the first antipsychotic treatment. In patients who discontinued treatment (n=23,030), the rate of treatment re-initiation was 74.2% (n=17,086). As the duration of the first antipsychotic treatment increased, the time to re-initiation of treatment decreased (β=-0.146, p<0.001); however, the rate of treatment reinitiation was relatively constant (hazard ratio=1.001, p<0.001). Conclusion: Long-term antipsychotic treatment was not significantly associated with the rate of treatment re-initiation but showed a negative association with the time to re-initiation of treatment. Further research is needed to better understand the optimal treatment duration for FES.

• Korean Journal of Environmental Agriculture
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• v.27 no.1
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• pp.27-34
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• 2008

To effectively treat the domestic sewage that was produced on a small-scale in farming and fishing village in order to encourage an ecologically friendly environment, a small-scale sewage treatment apparatus using natural purification methods that consisted of an aerobic and an anaerobic plots were constructed. The efficiency of sewage treatment according to the sewage loading was investigated to obtain the optimum sewage loading in small-scale sewage treatment apparatus. Removal rate of pollutants according to the sewage loading were in the order of $150\;Lm^{-2}day^{-1}{\fallingdotseq}300\;Lm^{-2}day^{-1}>600\;Lm^{-2}day^{-1}$. Therefore, the optimum sewage loading was 300 L m-2 day-1. Under the optimum sewage loading, removal rate of BOD, $COD_{Mn}$, turbidity, T-N and T-P were 99, 94, 99, 49 and 89%, respectively. However, to satisfy the water quality standard in effluent in small-sclae sewage treatment apparatus for domestic sewage treatment, the low removal efficiency of T-N and T-P must be improved. So to improve the removal rate of T-N and T-P, the efficiency of sewage treatment according to the improved sewage treatment process such as, re-treatment at aerobic plot, anaerobic condition of aerobic plot, changing the filter media sizes and the depths in anaerobic plot, and also addition of oyster shells to filter media at anaerobic plot were investigated. In case of 150 cm depth in anaerobic plot with filter medium A (effectivity particle size 1.50 mm) and addition of oyster shells to filter media at anaerobic plot, removal rate of T-N and T-P in both plots were increased by 10 and 3%, and 14 and 7% in comparison with 100 cm depth in anaerobic plot with filter medium B(effectivity particle size 0.95 mm), respectively. The optimum improved sewage treatment process in small-scale sewage treatment apparatus were 150 cm depth in anaerobic plot with filter medium A and addition of oyster shells to filter media at anaerobic plot.

• Journal of the Korean Society for Heat Treatment
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• v.18 no.5
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• pp.281-287
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• 2005

Titanium aluminium nitride((TiAl)N) film is anticipated as an advanced coating film with wear resistance used for drills, bites etc. and with corrosion resistance at a high temperature. In this study, (TiAl)N thin films were deposited both at room temperature and at elevated substrate temperatures of 573 to 773 K by using a two-facing-targets type DC sputtering system in a mixture Ar and $N_2$ gases. Atomic compositions of the binary Ti-Al alloy target is Al-rich (25Ti-75Al (atm%)). Process parameters such as precursor volume %, substrate temperature and Ar/$N_2$ gas ratio were optimized. The crystallization processes and phase transformations of (TiAl)N thin films were investigated by X-ray diffraction, field-emission scanning electron microscopy. The microhardness of (TiAl)N thin films were measured by a dynamic hardness tester. The films obtained with Ar/$N_2$ gas ratio of 1:3 and at 673 K substrate temperature showed the highest microhardness of $H_v$ 810. The crystallized and phase transformations of (TiAl)N thin films were $Ti_2AlN+AlN{\rightarrow}TiN+AlN$ for Ar/$N_2$ gas ratio of 1:3, $Ti_2AlN+AlN{\rightarrow}TiN+AlN{\rightarrow}Ti_2AlN+TiN+AlN$ for Ar/$N_2$ gas ratio of 1:1 and $TiN+AlN{\rightarrow}Ti_2AlN+TiN+AlN{\rightarrow}Ti_2AlN+AlN{\rightarrow}Ti_2AlN+TiN+AlN$ for Ar/$N_2$ gas ratio of 3:1. The above results are discussed in terms of crystallized phases and microhardness.

• Journal of Embryo Transfer
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• v.23 no.2
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• pp.109-114
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• 2008

This study examined pregnancy and fetal loss rates according to different estrus synchronization protocols and injection of gonadotropin releasing hormone (GnRH) after transfer of Korean Native Cattle embryos to Holstein recipients. In Experiment 1, recipients received no treatment (Control, n = 119); two injections of prostaglandin$F_{2{\alpha}}$ ($PGF_{2{\alpha}}$ ) 11 days apart (PGF group, n = 120); GnRH (day 0)-$PGF_{2{\alpha}}$ (day 7)-GnRH (day 9) (Ovsynch group, n = 120); and CIDR (day 0)-$PGF_{2{\alpha}}$ and CIDR removal (day 7)-GnRH (day 9) (CIDR group, n = 110). In Experiment 2, the control group was received no treatment of GnRH. The treatment groups were received GnRH at embryo transfer (ET) (day 0), 7 days later, 14 days later, ET and 7 days later, 7 and 14 days later, or ET, 7 and 14 days later. Recipients were assigned to treatment randomly and received two in vitro produced blastocysts. Pregnancy was diagnosed at day 60 by palpation per rectum. Fetal loss to term was determined by palpation every 90 days thereafter. In Experiment 1, the pregnancy rate in the CIDR group (59.1%) were higher than in the Control group (42.0%) (p<0.01); fetal loss rates were similar for all groups (12.0 to 18.5%). In Experiment 2, the pregnancy rate in Day 0+7+14 group was higher (60.2%) than the control (40.2%) (p<0.01) and resulted in a lower fetal loss (p<0.05) than the control (4.6 vs. 11.4%). There were no significant difference between other treatment and the control (p>0.05). These results show that pregnancy rates of bovine embryos can be enhanced by CIDR insertion or GnRH $3{\times}$ treatment. Additionally, fetal loss may be reduced with GnRH treatment after ET.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.4
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• pp.19-35
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• 2009

Objectives : This experimental study was designed to investigate the effect of KangwhalSokdan-tang(Jianghuoxuduan-tang) on the muscle regeneration of atrophied rat muscle by hindlimb suspension. Materials and methods : In this study, Sprague-Dawley rats weighing about 250g were subjected to hindlimb suspension and divided into total four groups: Normal group(n=6), Control group(n=6), Hindlimb non-treatment group(n=6), Hindlimb treatment group(n=6). Experiments were seperately tried two times. The first trial was studied by the following two groups; The first was normal group(n=6). The second was group(n=18) for hindlimb suspension during 2 weeks (control I group). The second trial after 2 weeks hindlimb suspension was studied by the following three groups; The third group(n=6) was expired immediately after 2 weeks hindlimb suspension. The forth group(n=6) was given free activity during 2 weeks after 2 weeks hindlimb suspension. The fifth group(n=6) was administrated of KST during 2 weeks after 2 weeks hindlimb suspension. In order to investigate degree of muscle atrophy, body weight and gastrocnemius muscle mass were compared. To analyze muscle regeneration factors(expression of IGF-1, Myogenin, MyoD), Western blot was used. Results : The results were analyzed by statistical process as follows, 1. In body weight, all hindlimb suspension groups were lower than normal group, but tendency of increase was shown in KST group compared to non-treatment group after 2 weeks hindlimb suspension. 2. In gastrocnemius muscle mass, KST group on both side was significantly higher than non-treatment group after 2 weeks hindlimb suspension. 3. In case of IGF-I, Type I of KST group was significantly increased than non-treatment group, but Type II was not shown significance. 4. There was no significantly difference in Myogenin. 5. In MyoD, Type I of KST group was significantly increased than control group, and Type II of KST group was significantly increased than non-treatment group. Conclusions : In summary, this study demonstrates that KST administration has an effect to prevent muscle atrophy and contribute muscle regeneration and proliferation. And also it is suggested that IGF-I and MyoD is major factors of myogenesis expression to KST adminstration after hindlimb suspension.