• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.6
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• pp.1407-1412
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• 2014

In order to improve spectrum sensitivity of photodiode for detection of the laser at 850 nm ~ 1000 nm of near-infrared wavelength band, this study has produced silicon-based fast film PIN photodiode and analyzed electrical and optical properties. The manufactured device is packaged in TO-18 type. The electrical properties of the dark currents both Anode 1 and Anode 2 have valued of approximately 0.055 nA for 5 V reverse bias, while the capacitance showed 19.5 pF at frequency range of 1 kHz and about 19.8 pF at the range of 200 kHz for 0 V. In addition, the rising time of output signal was verified to have fast response time of about 30 ns for 10 V. For the optical properties, the best spectrum sensitivity was 0.66 A/W for 880 nm, while it was relatively excellent value of 0.45 A/W for 1,000 nm.

• Journal of the Korean Chemical Society
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• v.39 no.12
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• pp.940-945
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• 1995

The SS-epm(N,N '-bis-[2(S)-pyrrolidinylmethyl]ethane-1,2-diamine) ligand having stereospecificity has been prepared and reacted with $CoCl_2{\cdot}6H_2O$ or trans-$[Co(pyridine)_4Cl_2]Cl.$ The resultants are green crystals, both of which are identified to be trans-$[Co(SS-epm)Cl_2]_2(COCl_4)$ by elemental analysis and absorption spectra. CD spectrum of trans complex shows negative (-) cotton effect at long wavelength due to the vicinal effect of the stereospecifically chelated ligands. The conformation of SS-epm in trans complex is ${\delta}{\lambda}{\delta}$(SRRS) for each of the five membered chelated ring. $Co(II)Cl_4^{2-}$ as counter ion plays an importance role in the ionic association of the formation of trans complex with SS-epm. Furthermore, according to orientation of secondary amine, total strain energy on each isomers was calculated by molecular mechanics (MM) to verify structural characterization and spectral data.

• Journal of the Korean Chemical Society
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• v.55 no.2
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• pp.230-234
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• 2011

The present study describes the synthesis of 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone derivatives. The synthesis of the first target compound, 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone (1), was achieved by Friedel-Crafts acylation of o-cresyl methyl ether with succinic anhydride and subsequent cyclization of the intermediary g-keto acid with hydrazine hydrate. Condensation of compound 1 with aromatic aldehydes in the presence of sodium ethoxide affords the corresponding 4-substituted benzyl pyridazinones (3a-d). The dihydropyridazinone 1 underwent dehydrogenation upon treatment with bromine/acetic acid mixture to give (4). Pyridazine (5) has been synthesized upon the reaction of pyridazinone (1) with 1,3-diphenyl-2-propen-1-one under the Michael addition reaction. N-dialkylaminomethyl derivatives 6a-b have been obtained from the reaction of pyridazinone 1 with formaldehyde and secondary amine, whereas reaction of 1 with formaldehyde gives N-hydroxymethyl derivative (7). This study also includes the synthesis of the 3-chloropyridazine derivative 8 in excellent yield by heating pyridazinone 3b in phosphorus oxychloride. The behaviour of the chloro derivative toward sodium azide, benzyl amine and anthranilic acid was also studied. The proposed structures of the products were confirmed by elemental analysis, spectral data and chemical evidence.

• Journal of the Korean Chemical Society
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• v.53 no.6
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• pp.683-692
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• 2009

The synthesis of a novel series of nickel(II) complexes with new ligands derived from hydrazones of isoniazid have been reported in present work. The complexes have general compositions [$Ni(L)_2X_2$] or $[Ni(L)_3](ClO_4)_2$ {L = N-isonicotinamido-furfuraldimine (INH-FFL), N-isonicotinamido-3',4',5'-trimethoxybenzaldimine (INH-TMB) or N-isonicotinamido-cinnamalidene (INH-CIN) and X = $Cl^-$, ${NO_3}^-$, $ NCS^-$ or $CH_3COO^-$}. The ligands hydrazones behave as neutral bidentates (N and O donor) through the carbonyl oxygen and azomethine nitrogen. The new complexes with octahedral geometry have been characterized by elemental analysis, molecular weight determinations, magnetic susceptibility/moment, thermogravimetric, electrochemical and spectroscopic studies viz. infrared and electronic spectra. On the basis of conductivity measurements in nitrobenzene ($PhNO_2$) solution the [$Ni(L)_2X_2$] and $[Ni(L)_3](ClO_4)_2$ complexes have been found to be non-electrolytes and 1:2 electrolytes, respectively. Thermal properties have also been investigated, which support the geometry of the complexes. Antibacterial and antifungal properties of nickel(II) complexes and few standard drugs have also been examined and it has been observed that the complexes have moderate antibacterial activities.

• Proceedings of the ESK Conference
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• 1993.10a
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• pp.223-235
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• 1993

요통(Lowback Pain)을 유발하는 주요원인으로 알려져있는 MMH(Manual Materials Handling) 작업에 있어서 작업조건의 변화가 근육의 활동과 피로도에 미치는 영향을 평가하기 위해 4가지 서로 다른 작업조건하에서 몸통부위(Trunk)의 주요근육에 대한 EMG 파형분석을 실시 하였다. 본 연구에서의 분석대항작업은 실제 작업조건과 유사하레 설계된 120분간의 단속적인 인양(Lifting)/하역(Lowering) 작업으로서 작업중량은 작업자의 MVIS(Maximum Voluntary Isometric Strength)를 기준으로 설정되었으며, 매 10분 간격으로 EMG 측정이 이루어졌다. 작업물이 작업자의 정면에 위치한 대칭형(Symmetric) 작업의 경우 배면부(Dorsal) 근육인 천극근(Erector Spinae)과 활배근(Latissimus Dorsi)이 활동근(Active Muscle)인 것으로 나타났으며, 정중면(Medial Plane)을 중심으로 좌우측 근육이 동일한 근력을 발휘하였다. 작업물이 작업자의 한쪽 측면에 위치한 90도 비대칭형(Asymmetric) 작업의 경우 천극근과 활배근외에 작업물과 반대쪽 외사근(External Oblique)이 활동근으로 추가되었으며, 작업물과 반대쪽의 근육들이 더욱 큰 근력을 발휘하였다. 작업의 반복에 따른 근육의 피로도를 평가하기 위해 실시한 EMG 파형의 Spectral Analysis 결과, 비대칭형 작업시 작업물과 반대쪽의 천극근에서 작업시간의 경과에 따라 중위주파수(Median Power Frequency)가 저주 파수대로 천이(Lower Shift)하는 현상이 나타났으며, 일정한 작업량이라도 작업중량을 줄이고 작업 빈도를 높여서 작업할 경우에 이러한 현상이 더욱 두드러졌다. 작업시간의 경과에 따른 MVIS의 감소 현상은 작업빈도가 높고 비대칭형 작업일 때 가장 크게 나타났다. 총손실을 줄이고, 상대적 비용절감효과를 갖게할 수 있다고 하였다. 따라서 본 연구에서는 성인 여성기성복의 치수적합성을 높이기위하여 출산 후 중년에 접어 들면서 체형이 변화되는 것을 고려하여 연령을 분류하고(18세-34세, 30세-51세), 각 연령 집단에 따른 체형을 각각 3가지로 분류하였다. 이에 따라 의복 생산시의 총손실을 줄이기위한 상의, 하의생산시 필요한 부위별 최적규격치 간격을 제시하였다.적인 기능으로 보여지는 것에 좁혀서 작업능력의 연령증가 변화에 대하여다원적 평가를 하는 것이 실제적이라고 할 수 있다. 따라서 본 연구에서는 인간이 가지고 있는 다수의 기능중에서 수지교 치성과 연령증가와의 관계를 조사한다. 만약 연령증가 만으로 수지교치성을 평가 할 수 없는 경우에는 어떠한 요인이 수지기민성의 변화에 영향을 미치는가를 검토한다.t list)에서 자동적으로 사건들의 순서가 결정되도록 확장하였으며, 설비 제어방식에 있어서도 FIFO, LIFO, 우선 순위 방식등을 선택할 수 있도록 확장하였다. SIMPLE는 자료구조 및 프로그램이 공개되어 있으므로 프로그래머가 원하는 기능을 쉽게 추가할 수 있는 장점도 있다. 아울러 SMPLE에서 새로이 추가된 자료구조와 함수 및 설비제어 방식등을 활용하여 실제 중형급 시스템에 대한 시뮬레이션 구현과 시스템 분석의 예를 보인다._3$", chain segment, with the activation energy of carriers from the shallow trap with 0.4[eV], in he amorphous regions.의 증발산율은 우기의 기상자료를 이용하여 구한 결과 0.05 - 0.10 mm/hr 의 범위로서 이로 인한 강우손실량은 큰 의미가 없음을 알았다.재발이 나타난 3례의 환자를 제외한 9례 (75%)에서는 현재까지 재발소견을 보이지 않고 있다. 이러한 결과는 다른 보고자들과 유사한 결과를

• Investigative Magnetic Resonance Imaging
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• v.20 no.2
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• pp.81-87
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• 2016

Purpose: To analyze the feasibility of three-dimensional (3D) diffusion-weighted (DW) PSIF (reversed FISP [fast imaging with steady-state free precession]) sequence in order to evaluate peripheral nerves in the elbow. Materials and Methods: Ten normal, asymptomatic volunteers were enrolled (6 men, 4 women, mean age 27.9 years). The following sequences of magnetic resonance images (MRI) of the elbow were obtained using a 3.0-T machine: 3D DW PSIF, 3D T2 SPACE (sampling perfection with application optimized contrasts using different flip angle evolution) with SPAIR (spectral adiabatic inversion recovery) and 2D T2 TSE (turbo spin echo) with modified Dixon (m-Dixon) sequence. Two observers used a 5-point grading system to analyze the image quality of the ulnar, median, and radial nerves. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of each nerve were measured. We compared 3D DW PSIF images with other sequences using the Wilcoxon-signed rank test and Friedman test. Inter-observer agreement was measured using intraclass correlation coefficient (ICC) analysis. Results: The mean 5-point scores of radial, median, and ulnar nerves in 3D DW PSIF (3.9/4.2/4.5, respectively) were higher than those in 3D T2 SPACE SPAIR (1.9/2.8/2.8) and 2D T2 TSE m-Dixon (1.7/2.8/2.9) sequences (P < 0.05). The mean SNR in 3D DW PSIF was lower than 3D T2 SPACE SPAIR, but there was no difference between 3D DW PSIF and 2D T2 TSE m-Dixon in all of the three nerves. The mean CNR in 3D DW PSIF was lower than 3D T2 SPACE SPAIR and 2D T2 TSE m-Dixon in the median and ulnar nerves, but no difference among the three sequences in the radial nerve. Conclusion: The three-dimensional DW PSIF sequence may be feasible to evaluate the peripheral nerves around the elbow in MR imaging. However, further optimization of the image quality (SNR, CNR) is required.

• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.594-602
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• 2011

The effect of ${\alpha}$-, ${\beta}$- and ${\gamma}$-picolines on the stereochemistry of the coordination compounds of lanthanide(III) nitrates derived from 4[N-(furfural)amino]antipyrine semicarbazone (FFAAPS) has been studied. The general composition of the present coordination compounds is [Ln(FFAAPS)$(NO_3)_3$Pic] (Ln=La, Pr, Nd, Sm, Gd, Tb, Dy or Ho and Pic=${\alpha}$-, ${\beta}$- or ${\gamma}$-picolines). All these coordination compounds have been characterized by elemental analyses, molecular weight, molar conductance, magnetic susceptibility, infrared and electronic spectra. The infrared studies suggest that the FFAAPS behaves as a neutral tridentate ligand with N, N, O donor while ${\alpha}$-, ${\beta}$- or ${\gamma}$-picoline is coordinated to the lanthanide(III) ions via heterocyclic N-atom. Nitrates are bicovalently bonded in these compounds. From the electronic spectral data, nephelauxetic effect (${\beta}$), covalence factor ($b^{1/2}$), Sinha parameter (${\delta}%$) and the covalence angular overlap parameter (${\eta}$) have been calculated. Thermal stabilities of these complexes have been studied by thermogravimetric analysis. The coordination number of lanthanide(III) ions in the present compound is found to be ten. The antibacterial studies screening of the primary ligand FFAAPS and the complexes showed that the present complexes have moderate antibacterial activities.

• Journal of Radiation Protection and Research
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• v.34 no.4
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• pp.190-194
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• 2009

Gamma spectral results for macroalgae samples taken from the environment of Ulchin nuclear power plants in Korea (east coast), showed 766 keV peaks, which were identified as $^{95}Nb$ by several research institutes. After the enhancement of liquid radioactive waste disposal facility at Ulchin NPP site, the $^{95}Nb$ amount in the liquid radioactive waste outflow has drastically reduced, but the expected reduction in $^{95}Nb$ specific activity from environmental samples did not actually show up on gamma spectroscopy. Detailed re-investigation revealed that along with 766 keV peak, other peaks (63, 92 and 1001 keV) from $^{234}Th-^{234}mPa$ decay series were also detected on spectroscopy, and that the measured half lives of the four peaks were very close to known half life of $^{234}Th-^{234}mPa$ decay series, which is 24.1 day. The measured gamma yield ratios of 766 keV peak to 1001 peak were very close to known ratio 0.35 for $^{234}mPa$. It is concluded that 766 keV peaks on gamma spectroscopy of Ulchin NPP environmental samples were mainly from $^{234}mPa$, which is one of naturally occurring radionuclides.

• Journal of the Korean Chemical Society
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• v.37 no.7
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• pp.655-661
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• 1993

The neutral monomeric compounds $[Mo(NO)_2Cl_2(phen)]$ and $[W(NO)_2Cl_2(phen)]$ (phen= 1,10-phenanthroline) have been prepared by reactions of polymeric compounds $[{Mo(NO)_2Cl_2}n],\;[{W(NO)_2Cl_2}n]$ with chelate ligands. Additions of one equivalent of silver(I) perchlorate to these cis-dinitrosyl compounds in acetone solution produce $[Mo(NO)_2(phen)(S)Cl][ClO_4]\;and\;[W(NO)_2(phen)(S)Cl][ClO_4]$ (S = acetone). The homo- and hetero-dinuclear complexes, $[Cl(phen)(NO)_2M(pyz)M'(NO)_2(phen)Cl][ClO_4]_2$ (M = Mo, W) and $[Cl(phen)(NO)_2M(pyz)M'(NO)_2(phen)Cl][C1O_4]_2$ (M = Mo, M' = W) have been prepared by these monocationic complexes with pyrazine ligand respectively. These complexes characterized by elemental analysis, $1^H-\;and\;^{13}C-NMR$, infrared, and UV-visible spectroscopy are reported. The spectral data indicate that homo- and hetero-dinuclear complexes were symmetrical structures of $C_{2v}$.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.5
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• pp.474-485
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• 2014

Temporal and spatial variations of temperature and salinity around Ganjeol Point during January, April, August and November 2011 were studied using the data from CTD observations and temperature monitoring buoys deployed at 20 stations in the southeast coast of Korea. Temperature and salinity were nearly homogeneous through the whole depth by mixing of the seawater in spring and winter related to the sea surface cooling. Stratification induced by the river runoff and the bottom cold water was clear in summer. In autumn, sea water had vertical mixing initiated from surface layer and weak stratification at the middle and bottom layers. Low temperature and high salinity emerged throughout the year near Ganjeol Point, which inferred from turbulent mixing and upwelling by its topographical effect. Major periods of 1/4~1.4 day temperature fluctuations were recorded for the most part of the stations. According to the cross spectral density analysis, high coherence and small time lag for temperature fluctuation between layers were shown at Ganjeol Point. However, those features at the northen area of Hoeya river were opposed to Ganjeol Point. From analyses, thermohaline structure and its fluctuation around Ganjeol Point were characterized into those three parts, the south of Ganjeol Point, Ganjeol Point and the north of Ganjeol Point.