• Nuclear Engineering and Technology
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• 제55권8호
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• pp.3030-3038
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• 2023

Nowadays, mobile robots have been used to search for uncontrolled radioactive source in indoor environments to avoid radiation exposure for technicians. However, in the indoor environments, especially in the presence of obstacles, how to make the robots with limited sensing capabilities automatically search for the radioactive source remains a major challenge. Also, the source search efficiency of robots needs to be further improved to meet practical scenarios such as limited exploration time. This paper proposes an automatic source search strategy, abbreviated as ACA: the location of source is estimated by a convolutional neural network (CNN), and the path is planned by the A-star algorithm. First, the search area is represented as an occupancy grid map. Then, the radiation dose distribution of the radioactive source in the occupancy grid map is obtained by Monte Carlo (MC) method simulation, and multiple sets of radiation data are collected through the eight neighborhood self-avoiding random walk (ENSAW) algorithm as the radiation data set. Further, the radiation data set is fed into the designed CNN architecture to train the network model in advance. When the searcher enters the search area where the radioactive source exists, the location of source is estimated by the network model and the search path is planned by the A-star algorithm, and this process is iterated continuously until the searcher reaches the location of radioactive source. The experimental results show that the average number of radiometric measurements and the average number of moving steps of the ACA algorithm are only 2.1% and 33.2% of those of the gradient search (GS) algorithm in the indoor environment without obstacles. In the indoor environment shielded by concrete walls, the GS algorithm fails to search for the source, while the ACA algorithm successfully searches for the source with fewer moving steps and sparse radiometric data.

• 공업화학
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• 제8권4호
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• pp.700-703
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• 1997

Phthalic anhydride를 출발물질로 halogenation, phosphorylation하여 diethyl phthalimidoalkylphosphonate를 합성하였다. 이 화합물을 chlorination하여 O-ethyl phthalimidoalkylphosphonate을 만든후 diphenylmethyl 7-$\beta$-amino-3-acetoxymethyl-3-cephem-4-carboxylate와 coupling하여 지금까지 알려져 있지 않은 화합물 diphenylmethyl-7-$\beta$-(O-ethylphthalimidomethylphosphony1)-3-acetoxymethyl-3-cephem-4-carboxylate와 diphenylmethyl-7-$\beta$-[O-ethylphthalimidoethylphosphonyl]-3-acetoxymethyl-3-cephem-4-carboxylate를 각각 19%, 43%의 수율로 합성하였다.

• 한국정보컨버전스학회:학술대회논문집
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• 한국정보컨버전스학회 2008년도 International conference on information convergence
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• pp.53-56
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• 2008

This paper reports on the ACQA(Animated agent for Conversational Question Answering) project conducted at LIMSI. The aim is to design an expressive animated conversational agent(ACA) for conducting research along two main lines: 1/ perceptual experiments(eg perception of expressivity and 3D movements in both audio and visual channels): 2/ design of human-computer interfaces requiring head models at different resolutions and the integration of the talking head in virtual scenes. The target application of this expressive ACA is a real-time question and answer speech based system developed at LIMSI(RITEL). The architecture of the system is based on distributed modules exchanging messages through a network protocol. The main components of the system are: RITEL a question and answer system searching raw text, which is able to produce a text(the answer) and attitudinal information; this attitudinal information is then processed for delivering expressive tags; the text is converted into phoneme, viseme, and prosodic descriptions. Audio speech is generated by the LIMSI selection-concatenation text-to-speech engine. Visual speech is using MPEG4 keypoint-based animation, and is rendered in real-time by Virtual Choreographer (VirChor), a GPU-based 3D engine. Finally, visual and audio speech is played in a 3D audio and visual scene. The project also puts a lot of effort for realistic visual and audio 3D rendering. A new model of phoneme-dependant human radiation patterns is included in the speech synthesis system, so that the ACA can move in the virtual scene with realistic 3D visual and audio rendering.

• The Journal of Korean Physical Therapy
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• 제17권2호
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• pp.126-147
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• 2005

TCD(transcranial doppler, TCD) units is a equipment that measure a blood flow velocity in the middle cerebral artery(MCA), anterior cerebral artery(ACA), posterior cerebral artery(PCA), and vertebral artery(VA). The aim of this study was to determine the influence on cerebral blood flow velocity according to different stimulation frequency of interferential currents. 50 patients who has a cervical pain were participated in this study and randomly divided into one of the three experimental, placebo, and control group: (1)IFS 1; $10{\sim}30Hz$ was applied, (2)IFS 2; $30{\sim}50Hz$ was applied, (3)IFS 3; $50{\sim}100Hz$ was applied, (4)placebo; suction only applied, and (5)control; neither suction nor interferential stimulation applied. In the IFS groups, interferential stimulations were applied through four suction electrodes application from the 5th cervical to the 1st thoracic level. The results were as follow; 1. MCA was statistically significant with IFS 1, IFS 2, IFS 3, and Placebo group(p<0.05), But there was no statistical significance between IFS 1 and IFS 3 group(p>0.05). 2. ACA was statistically significant with IFS 1, IFS 2, and IFS 3 group(p<0.05). And IFS 1 was more statistical significance than IFS 3 group on ACA(p<0.05). 3. PCA was statistically significant with IFS 1, IFS 2, and IFS 3 group(p<0.05). And IFS 1 was more statistical significance than IFS 3 group on PCA(p<0.05). 4. VA was statistically significant with IFS 1, IFS 2, and IFS 3 group(p<0.05). And IFS 1 was more statistical significance than IFS 3 group on VA(p<0.05).

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.407-410
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• 2011

An isolable activated ester, diethyl thiophosphoryl [(Z)-(2-aminothiazol-4-yl)-2-(methoxyimino)acetate (9a, DAMA) was prepared in high purity, which was at least stable for 7 d at $25^{\circ}C$ and 6 months at $5^{\circ}C$. Its reaction with 7-ACA (4) in the presence of tributylamine in i-PrOH provided cefotaxime (1) of high purity in good yield. Preparation of DAMA and its reaction with 7-ACA (4) to 1 was performed in one-pot manner, respectively with minimal unit operations of stirring and filtration.

• 대한화학회지
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• 제38권8호
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• pp.603-607
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• 1994

새로운 cephalosporin 항생물질인 7-[(3,4-dihydro-6-methoxycarbonyl-2,2-dimethyl-2H-1,4-thiazin-3-yl)acetamido]-3-[(substituted pyrimidin-2-yl)thiomethyl]-3-cephem-4-carboxylic acid derivatives(2a∼2d)유도체들을 합성하였다. 7-ACA의 3-위치에는 pyridinylthiomethyl기를 도입시키고, 7-위치에는 thiazine를 치환시켜서 구조 변화에 대한 항균 활성을 측정하였다. 그 결과 이들 유도체들은 기준물질인 cefotaxim보다 낮은 항균력을 나타내었다.

• 약학회지
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• 제50권6호
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• pp.393-397
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• 2006

The synthesis of new 3-substituted 7-halocephalosporanates was described. 7-ACA was reacted with thiols at pH 6.5${\sim}$6.8 to afford the 3-substituted 7-ACA (1), which was treated with diphenyldiazomethane to give diphenylmethyl 7-aminocephalosporanate (2). The Halogenation of 7-aminocephalosporanate (2) with NaNO$_2$, KBr and H$_2$SO$_4$ gave 7-bro-mocephalosporanate (3) and with NaNO$_2$, HCI gave 7-chlorocephalosporanate (4). Diphenylmethyl cephalosporanate (2${\sim}$4) were deprotected by AIC1$_3$ in anisole and neutralized to give the sodium cephalosporanate (5${\sim}$7).

• Journal of the Korean Statistical Society
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• 제20권2호
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• pp.162-176
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• 1991

The problem of determining the number of clusters, K. is the main objective of this study. Attention is focused on the use of Rand(1971)'s $C_{k}$ statistic with some agglomerative clustering algorithms(ACA) defined in the ($\beta$, $\pi$) plane in predicting the number of clusters within the given set of data. The (k, $C_{k}$) plots for k=1, 2, …, N are explored by a Monte Carlo study. Based on its performance, the use of $C_{k}$ with the pair of ACA, (-.5, .75) and (-.25, .0), is recommended for predicting the number of clusters present within a set of data. data.

• 한국미생물·생명공학회지
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• 제23권5호
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• pp.556-558
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• 1995

A strain which showed cephalosporin C resistance and 7-aminocephalosporanic acid sensitivity was isolated from nature. Among the isolates, SS5 was sensitive to cephalosporin C, penicillin G, ampicillin, 7-aminocephalosporanic acid, 6-aminopenicillanic acid, and 7-aminodeacetoxy cephatosporanic acid at concentrations of 1,000 $\mu $g/ml, 2,000 $\mu $g/ml, 3,000 $\mu $g/ml, 30 $\mu $g/ml 100 $\mu $g/ml and 100 $\mu $g/ml, respectively. But SS5 was sensitive at very low concentration of chloramphenicol, kanamycin, neomycin, streptomycin and tetracycline. Since SS5 was sensitive to 7-ACA (30 $\mu $g/ml) and didn't have $\beta $-lactamase activity on the cephalosporin C, SS5 could be useful as an indicator strain for the production of 7-ACA, which is an important precursor for the synthesis of many semisynthetic cephalosporins.

• 생약학회지
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• 제25권1호
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• pp.35-40
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• 1994

Aqueous extreact of fresh ginseng (AFG) was examined for the antigenicity in Hartley guinea pigs in comparision with ovalbumin (OVA). When guinea pigs were sensitized with AFG emulsified with complete Freund's adjuvant (CFA), these animals showed negative reactions in active systemic anaphylaxis (ASA), active cutaneous anaphylaxis (ACA) and passive cutaneous anaphylaxis (PCA) tests and passive hemagglutination (PHA) reaction. On the contrary, when guinea pigs were sensitized with OVA emulsified with CFA as positive controls, these animals disclosed positive reactions in ASA, ACA and PCA tests and PHA reaction. From these results, AFG was considered not to possess antigenic properties in guinea pigs. In addition, the dose levels of AFG empolyed in the present experiment were confirmed not to suppress immune reactions.