• Proceedings of the Korean Society for Information Management Conference
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• 2014.08a
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• pp.99-102
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• 2014

이 연구는 서울과 경기 지역 어린이도서관의 질의응답서비스인 Q & A의 내용을 분석함으로써 어린이 도서관의 질의 경향에 대해 연구하고자 한다.

• Applied Chemistry for Engineering
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• v.10 no.7
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• pp.996-1002
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• 1999

The oxalate precipitation of lanthanide and actinide by oxalic acid was investigated in the simulated radioactive liquid waste, which was composed of 17 elements of alkali, alkaline earth(Cs, Rb, Ba, Sr), transition metal(Zr, Fe, Mo, Ni, Pd, Rh), lanthanide(La, Y, Nd, Ce, Eu) and actinide(Np, Am) in nitric acid solution. The effect of concentrations of nitric acid and ascorbic acid on the precipitation yield of each element in the simulated solution was examined at 0.5 M oxalic acid concentration. The precipitation yields of the elements were usually decreased with nitric acid concentration, nevertheless, the precipitation yields of lanthanide and actinide were more than 99%. Palladium was precipitated due to the reduction of Pd(II) into Pd metal by the addition of ascorbic acid in the oxalate precipitation and then, the precipitation yields of Mo, Fe, Ni, Ba decreased by 10~20% with concentration of ascorbic acid. The reductive precipitation of Pd(II) into Pd metal by the addition of ascorbic acid into the simulated radwaste occurred at below 1 M nitric acid concentration and its yield showed maximum at the ascorbic acid concentration of 0.01~0.02 M. The hydrazine suppressed the reductive precipitation of Pd by the ascorbic acid.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.128-132
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• 2010

Purpose: Nuclear medicine general operation room is radioactive control room which is used for the handling of radioisotope(R.I). Radioactive contamination materials must be under control and separated from general trash. With this experiments, we want to actively suggest the guideline of controling and operating radioactive contamination materials by measuring contamination degree and analyzing the causes which is not realized so far. Materials and Methods: Materials are selected from Oct. 2009 to March. 2010. salines which are used for labelling radiophamaceuticals and generator cap, saline needle cap, $^{99m}Tc$-needle cap saline vial which is generated from $^{99}Mo$/$^{99m}Tc$ generator. After measuring each surface contamination degree by survey meter, mean value and standard deviation one were solved out. Results: In result, After measuring surface contamination degree, radioactivity of saline for labelling radiophamaceuticals showed $14429{\pm}26378$ cpm (p<0.05) and in measured generators, foreign imported things showed that generator cap : $9{\pm}21$ cpm, saline vial : $17{\pm}28$ cpm. saline needle cap : $35{\pm}66$ cpm, $^{99m}Tc$-needle cap : $9{\pm}21$ cpm, saline vial $13{\pm}28$ cpm. domestic things showed that generator cap : $22852{\pm}52545$ cpm, saline needle cap : $87367{\pm}109711$ cpm, $^{99m}Tc$-needle cap : $9008{\pm}10459$ cpm, saline vial : $186416{\pm}158196$ cpm (p<0.05). Conclusion: The saline which is used for labelling, exceeded 1/10 of maximum permissible range. this is generated from radiophamaceuticals dilution procedure. and In generators, radioactive value of foreign import things showed closely background value. but which of domestic thing showed that exceeded more than 1000 values 1/10 of maximum permissible range. the causes of that is domestic generator is contaminated in manufacturing procedure. So, to dispose radioactive contamination materials which is could betaken out of, the control and operation must be radical under controlled by radioactive measuring, recording and equipping of its own. if this is kept well, we can prevent surely that radioactive waste could be disposed like as general trash.

• The Korean Journal of Nuclear Medicine
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• v.28 no.1
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• pp.22-30
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• 1994

Encephalo-duro-arterio-synangiosis (EDAS) is a relatively new surgical procedure for treatment of childhood moyamoya disease. We assessed regional cerebral perfusion in moyamoya patients before (1.3 mo) and after (6.8 mo) EDAS with $^{99m}Tc$-HMPAO brain SPECT. A total of 21 EDAS operations in 17 moyamoya patients was included. Preoperative CT or MRI showed cerebral infarction in 14 patients and carotid angiography showed Suzuki grade I to V stenosis in 6%, 9%, 62%, 12% and 12% of the hemispheres respectively. Preoperative SPECT showed regional hypoperfusion in all patients, bilateral frontal and temporal lobes being the most frequently involved site. $4{\times}4$ pixel sized ROIs were applied on the frontotemporal cortex in 3 slice averaged transverse tomographic images. An index of regional perfusion was measured as: PI (%)=average F-T activity/average cerebellar activity${\times}100$ Pre-EDAS ipsilateral PI ranged from 23.7 to 98.4% (mean: $74.3{\pm}17%$) and increased significantly after operation ($81.4{\pm}17%$, p<0.001). Individual post-EDAS PI improved in 15/21 cases, showed no significant change in 5 and was slightly aggravated in 1. The amount of clinical improvement (${\Delta}CI$) was graded with a scale of 0 to 4 based on frequency and severity of TIA attacks. When patients were grouped according to pre-EDAS PI, group II (PI 70-89) showed a significantly higher ${\Delta}CI$ (3.3) compared to group I (PI< 70, 1.57) or group III (PI >90, 0.5) (P< 0.001). The amount of perfusion improvement (${\Delta}PI$) showed significant correlation with ${\Delta}CI$ (r=0.42, p=0.04). ${\Delta}PI$ did not, however, correlate with the amount of neovascularization assessed angiographically in 8 patients. Serial HMPAO SPECT is an useful noninvasive study for assessing perfusion improvement after EDAS in childhood moyamoya patients.

• Journal of Korea Spatial Information System Society
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• v.11 no.2
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• pp.99-110
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• 2009

Currently, there are many applications being developed based on sensor network technology. A tracking method for moving objects in sensor network is one of the main issue of this field. There is a little research on this issue, but most of the existing work has two problems. The first problem is a communication overhead for visiting sensor nodes many times to track a moving object. The second problem is an disability for dealing with many moving objects at a time. To resolve the problems, we, in this paper, propose a signature-based tracking method using efficient data aggregation for moving objects, called SigMO-TRK. For this, we first design a local routing hierarchy tree to aggregate moving objects' trajectories efficiently by using a space filtering technique. Secondly, we do the tracking of all trajectories of moving objects by using signature in a efficient way, our approach generates signatures to method. In addition, by extending the SigMO-TRK, we can retrieve the similar trajectories of moving objects for given a query. Finally, by using the TOSSIM simulator, we show that our signature-based tracking method outperforms the existing tracking method in terms of energy efficiency.

• The Korean Journal of Nuclear Medicine Technology
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• v.20 no.2
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• pp.36-41
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• 2016

Purpose Sentinel lymphoscintigraphy (SLS) was using only $^{99m}Tc-phytate$. If the supply is interrupted temporarily, there is no alternative radiopharmaceuticals. The aim of this study measure the particle size of radiopharmaceuticals and look for radiopharmaceuticals which can be substituted for $^{99m}Tc-phytate$. Materials and Methods The particle size of radiopharmaceuticals were analyzed by a nano-particle analyzer. This study were selected known radiopharmaceuticals to be useful particle size for SLS. We were divided into control and experimental groups using $^{99m}Tc-DPD$, $^{99m}Tc-MAG3$, $^{99m}Tc-DMSA$ with $^{99m}Tc-phytate$. For in-vivo experiment, radiopharmaceuticals were injected intradermally at both foot to perform lymphoscintigraphy. Imaging was acquired to dynamic and delayed static image and observe the inguinal lymph nodes with the naked eye. Results Particle size was measured respectively Phytate 105~255 nm (81.9%), MAG3 91~255 nm (98.7%), DPD 105~342 nm (77.3%), DMSA 164~ 342 nm (99.2%), MAA 1281~2305 nm (90.6%), DTPA 342~1106 nm (79.4%), and HDP 295~955 nm (94%). In-vivo delayed static image, inguinal lymph nodes of all experiment groups and two control groups are visible to naked eye. however, $^{99m}Tc-MAG3$ of control groups is not visible to naked eye. Conclusion We were analyzed to the particle size of the radiopharmaceuticals that are used in in-vivo. Consequently, $^{99m}Tc-DPD$, $^{99m}Tc-DMSA $are possible in an alternative radiopharmaceuticals of emergency.

• Journal of Energy Engineering
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• v.10 no.4
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• pp.370-378
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• 2001

Characteristics and synergistic effects of the coliquefaction of Alaskan subbituminous coal, wasted tire, and polypropylene were investigated in a tubing-bomb reactor at 41$0^{\circ}C$, and the coliquefaction reactions were performed at 37$0^{\circ}C$~45$0^{\circ}C$ to evaluate the coliquefaction mechanism. The coliquefaction kinetic model based on the free-radical theory was proposed and simulated by the non-linear parameter estimation method. Simulated results represented experimental ones successfully with the correlation coefficient of 0.99. When a catalyst was not used, the conversions were decreased as tetralin increase due to the decrease of liquefaction of polypropylene. When naphthenate catalysts of Mo, Co, and Fe were used, the coliquefaction conversions were increased with the increase of the liquefaction of polypropylene. When Co-naphthenate catalyst was used, the increase of the coliquefaction conversion were as high as 21~23%.

• Applied Chemistry for Engineering
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• v.9 no.2
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• pp.243-248
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• 1998

This study investigated the separation and the property of palladium precipitate formed by ascorbic acid in a simulated radioactive liquid waste, which was composed of 10 elements((Pd, Ru, Rh, Nd, Cs, Sr, Fe, Ni, Zr, Mo). Pd was separated selectively by using reduction characteristics of metal ions contained in the simulated waste with ascorbic acid. When the nitric acid concentration was 0.5 M, the Pd over 99.5% was precipitated by adding 0.04 M ascorbic acid. Nitric acid concentration is important at the reduction reaction of Pd ion. The precipitation yield of Pd was decreased as the concentration of nitric acid was increased. The Pd precipitate was re-dissolved in reaching at an equilibrium when the concentration of nitric acid was high and ascorbic acid was added with a small amount. The Pd precipitate formed by ascorbic acid was Pd metal and was aggregated by particles less than $1.0{\mu}m$.

• Korean Journal of Crystallography
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• v.9 no.1
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• pp.15-20
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• 1998

Single crystals of lithium heptaborate, Li3B7O12(M=288.49), have been grown and their structure was determined by the x-ray powder diffraction and the single crystal diffraction technique. It is found that the borate anion consists of two(B3O7)3- and (B3O8)5- groups a unit cell. The space group was determined to be P-1(Ci1) with a=6.500(3) Å, b=7.839(2) Å, c=8.512(1) Å, α=92.07(2)˚, β=104.97(2)˚, γ=99.35(3)˚, V=412.0(2) Å3, Z=2 Dx=2.32 g cm-3, MoKα, λ=0.71069 Å, μ=2.15cm-1, T=293K. The structure was refined to R=0.0339 and wR=0.0882 for 2296 unique reflections by the single crystal diffraction. By the x-ray powder diffraction, we could obtain the similar results.

• Korean Journal of Crystallography
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• v.9 no.1
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• pp.71-76
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• 1998

Crystal structure of Bis(ethylenediamine)palladium(II)-Bis(oxalato)palladate(II0 has been determined by X-ray crystallography. Crystal data : (Pd(C2H8N2)2.Pd(C2O4)2), Fw=509.04, Monocline, Space Group P21/c (no=14), a=6.959(2), b=13.506(2), c=15.339(2) Å, β=99.94(3), Z=4, V=1420 Å3, Dc=2.380 gcm-3, μ=25.46cm-1, F(000)=992. The intensity data were collected with Mo-Kα radiation (λ=0.7107 Å) on an automatic four-circle diffractometer with a graphite monochromater. The structure was solved by Patterson method and refined by full matrix least-square methods using unit weights. The final R and S values were R=0.021, Rw=0.030, Rall=0.032 abd S=2.1 for 1472 observed reflections. The essentially planar complex anions form diade of interplanar distances of 3.41 Å and their diads are stacked along aaxis with interplanar separation of 3.44 Å.