• Title/Summary/Keyword: long-term experiments

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A Potential Role of Oxytocin and Acupuncture in Drug Addiction (옥시토신의 약물중독에서 역할과 침(鍼) 관련성)

  • Yang, Chae-Ha;Choi, Seong-Hun
    • Korean Journal of Oriental Medicine
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    • v.15 no.3
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    • pp.53-61
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    • 2009
  • Oxytocin(OT), classically known to stimulate labour and milk ejection, contributes to play an important role in a wide range of behavioral effects including drug addiction. An increasing body of evidence suggests that OT ameliorates acute and long-term effects of commonly used drugs by means of interacting with the mesolimbic dopamine system. Mesolimbic dopamine system is thought to play a major role in the reinforcing properties of drug abuse. Oxytocin receptors in the nucleus accumbens(NAc) and ventral tegmental area(VTA) have been implicated in the regulation of reinforcing effects in abused drugs. In the same way acupuncture may attenuate the reinforcing effects of abused drugs in the NAc and VTA. We have an interest in similar liaison between the substrates of acupuncture and drug addiction that may involve OT. Here, we described the possibility that acupuncture modulates the reinforcing and sensitizing properties of abused drugs in the dopaminergic system via the regulation of activities in the oxytocinergic system. The elements in this paper are summarized as follows : neuroanatomical studies of oxytocinergic innervation and distribution of oxytocin receptors; experiments related to the methamphetamine, cocaine, morphine and ethanol; experiments related to the oxytocin and acupuncture.

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Particle Separation Characteristics and Harvesting Efficiency of Spirulina platensis Using Micro-bubble (미세기포를 이용한 Spirulina platensis의 입자 부상분리 특성 및 수거효율)

  • Gwak, Gyu-Dong;Kim, Mi-Sug;Kwak, Dong-Heui
    • Journal of Korean Society of Water and Wastewater
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    • v.27 no.5
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    • pp.621-629
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    • 2013
  • Since algae had been issued an environmental problem, water blooms, deepened due to increase of retention water basin in Korea as well as a biomass resource for producing biofuel, this study conducted a series of experiments for Spirulina platensis using the flotation process with micro-bubble. To elevate utilization of collected-algae, this study focused on omitting or minimizing coagulant's doses as changing a cultivation period and condition affected on physical property change of algae. Two coagulants, PAC and Chitosan, were used to test the collecting rate of algae and the result found no difference between two rates. For flotation experiments without adding the coagulant, dried algae weight (passing 14 days after cultivation for 20 days) detected high separation efficiency 98.2 % and it (passing 7 days after long-term cultivation for 28 days) presented good separation efficiency 91.9 %. Chlorophyll's separation efficiency showed a similar tendency with the case of the dried algae weight. In endogeny conditions, a light source and a carbon source were not considerably affected on the flotation separation efficiency. Thus, this study confirms that algae biomass may be collected without the coagulant during the endogeny condition period after enough cultivation time, 3 weeks.

Effect of particle size and saturation conditions on the breakage factor of weak rockfill materials under one-dimensional compression testing

  • Rahmani, Hamidreza;Panah, Ali Komak
    • Geomechanics and Engineering
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    • v.21 no.4
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    • pp.315-326
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    • 2020
  • The long-term behavior of rockfill material used in the construction of infrastructures such as dams is of great significance. Because of concerns about the application of weak rockfill material in dam construction, further experimental studies on the behavior of these materials are required. In this study, laboratory experiments were performed to investigate the one-dimensional deformation and particle breakage of the weak rockfill material under stress. A one-dimensional compression apparatus was designed and developed for testing of rockfill materials of different maximum particle sizes (MPSs). The compression tests were performed under dry, wet and saturated conditions on samples of rockfill material obtained from a dam construction site in Iran. The results of the experiments conducted at the specimen preparation stage and the 1D compression tests are presented. In weak rockfill, the effect of the addition of water on the behavior of the material was uncertain as there were both an increases and decreases observed in particle breakage. Increasing the MPS of the weak rockfill materials increased particle breakage, which was similar to the behavior of strong rockfill material. In all of the MPSs examined, the settlement of specimens under wet conditions was higher than that observed under dry conditions. Also, the greatest deformation occurred during the first hour of loading.

A Review on Degradation of Silicon Photovoltaic Modules

  • Yousuf, Hasnain;Khokhar, Muhammad Quddamah;Zahid, Muhammad Aleem;Kim, Jaeun;Kim, Youngkuk;Cho, Sung Bae;Cho, Young Hyun;Cho, Eun-Chel;Yi, Junsin
    • New & Renewable Energy
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    • v.17 no.1
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    • pp.19-32
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    • 2021
  • Photovoltaic (PV) panels are generally treated as the most dependable components of PV systems; therefore, investigations are necessary to understand and emphasize the degradation of PV cells. In almost all specific deprivation models, humidity and temperature are the two major factors that are responsible for PV module degradation. However, even if the degradation mode of a PV module is determined, it is challenging to research them in practice. Long-term response experiments should thus be conducted to investigate the influences of the incidence, rates of change, and different degradation methods of PV modules on energy production; such models can help avoid lengthy experiments to investigate the degradation of PV panels under actual working conditions. From the review, it was found that the degradation rate of PV modules in climates where the annual average ambient temperature remained low was -1.05% to -1.16% per year, and the degree of deterioration of PV modules in climates with high average annual ambient temperatures was -1.35% to -1.46% per year; however, PV manufacturers currently claim degradation rates of up to -0.5% per year.

Experimental and numerical study of autopilot using Extended Kalman Filter trained neural networks for surface vessels

  • Wang, Yuanyuan;Chai, Shuhong;Nguyen, Hung Duc
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.12 no.1
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    • pp.314-324
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    • 2020
  • Due to the nonlinearity and environmental uncertainties, the design of the ship's steering controller is a long-term challenge. The purpose of this study is to design an intelligent autopilot based on Extended Kalman Filter (EKF) trained Radial Basis Function Neural Network (RBFNN) control algorithm. The newly developed free running model scaled surface vessel was employed to execute the motion control experiments. After describing the design of the EKF trained RBFNN autopilot, the performances of the proposed control system were investigated by conducting experiments using the physical model on lake and simulations using the corresponding mathematical model. The results demonstrate that the developed control system is feasible to be used for the ship's motion control in the presences of environmental disturbances. Moreover, in comparison with the Back-Propagation (BP) neural networks and Proportional-Derivative (PD) based control methods, the EKF RBFNN based control method shows better performance regarding course keeping and trajectory tracking.

Emotion Recognition in Arabic Speech from Saudi Dialect Corpus Using Machine Learning and Deep Learning Algorithms

  • Hanaa Alamri;Hanan S. Alshanbari
    • International Journal of Computer Science & Network Security
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    • v.23 no.8
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    • pp.9-16
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    • 2023
  • Speech can actively elicit feelings and attitudes by using words. It is important for researchers to identify the emotional content contained in speech signals as well as the sort of emotion that resulted from the speech that was made. In this study, we studied the emotion recognition system using a database in Arabic, especially in the Saudi dialect, the database is from a YouTube channel called Telfaz11, The four emotions that were examined were anger, happiness, sadness, and neutral. In our experiments, we extracted features from audio signals, such as Mel Frequency Cepstral Coefficient (MFCC) and Zero-Crossing Rate (ZCR), then we classified emotions using many classification algorithms such as machine learning algorithms (Support Vector Machine (SVM) and K-Nearest Neighbor (KNN)) and deep learning algorithms such as (Convolution Neural Network (CNN) and Long Short-Term Memory (LSTM)). Our Experiments showed that the MFCC feature extraction method and CNN model obtained the best accuracy result with 95%, proving the effectiveness of this classification system in recognizing Arabic spoken emotions.

Multiscale modeling of smectite illitization in bentonite buffer of engineered barrier system

  • Xinwei Xiong;Jiahui You;Kyung Jae Lee;Jin-Seop Kim
    • Nuclear Engineering and Technology
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    • v.56 no.8
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    • pp.3242-3254
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    • 2024
  • With the increasing usage of nuclear energy, how to properly dispose nuclear waste becomes a critical issue. In this study, a multiscale modeling approach combining the experimental findings is presented to address the illitization process, its impact on transport properties, and system behavior of bentonite buffer in engineered barrier systems (EBS). Through the pore-scale modeling, reactive transport properties such as illite generation rate and effective diffusion coefficient of potassium ion as a function of porosity and temperature are quantified by employing the findings of hydrothermal reaction experiments of Bentonil-WRK. The capability of pore-scale modeling has been developed based on the Darcy-Brinkmann-Stokes equation, involving the processes of smectite illitization and clay swelling. Obtained reactive transport properties are utilized as input parameters for the macroscale modeling to predict the long-term behavior of bentonite buffer in EBS. As such, this study involves the whole workflow of quantifying the reaction parameters of smectite illitization through the hydrothermal reaction experiments, and numerically modeling the reactive transport process of smectite illitization in bentonite buffer of EBS from pore-scale to macroscale. The presented multiscale modeling findings are expected to provide reliable solution for safe nuclear waste disposal with EBS.

Effects of Rice Straw Compost Application on Exchangeable Potassium in Long-term Fertilization Experiments of Paddy Soils

  • Kim, Myung-Sook;Park, Seong-Jin;Lee, Chang-Hoon;Ko, Byong-Gu;Yun, Sun-Gang
    • Korean Journal of Soil Science and Fertilizer
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    • v.49 no.2
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    • pp.194-199
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    • 2016
  • In an experiment conducted at the research field of the National Institute of Agricultural Science, we investigated the effects of mineral fertilizer and rice straw compost on exchangeable potassium and K balances, and rice grain yield under a rice single system. The treatments were no fertilization (No fert.), inorganic fertilization (N), inorganic fertilizer (N, P, K) plus rice straw compost at rates of 7.5, 15.0, 22.5, and $30.0ton\;ha^{-1}$ (NPKC7.5, NPKC15.0, NPKC22.5, and NPKC30.0, respectively). The inorganic fertilizers(N, P, K) were added with standard fertilizer application rate in which nitrogen (N), phosphate ($P_2O_5$), and potassium ($K_2O$) were applied with $75{\sim}150kg\;ha^{-1}$, $70{\sim}86kg\;ha^{-1}$, $75{\sim}86kg\;ha^{-1}$, respectively. Exchangeable potassium for NPKC15.0 NPKC22.5, and NPK30.0 treatments was higher by $0.05{\sim}0.19cmol_c\;kg^{-1}$ than that of NPKC7.5 treatment. Increasing levels of rice straw compost resulted in an increase in the K balance from - $19.9kg\;ha^{-1}yr^{-1}$ (No fert.) to $41.9kg\;ha^{-1}yr^{-1}$ at NPKC22.5 treatment and $62.9kg\;ha^{-1}$ at NPKC30.0 treatment. Continuous application of rice straw compost with NPK fertilizers affected significantly the rice grain yields. The result of the study imply that the application of more than $22.5ton\;ha^{-1}$ of rice straw compost with NPK fertilizers are recommended as the best fertilization practice for enhancement of crop production and K supplying power of soil in the continuous rice cropping system.

Characterization of Crop Residue-Derived Biochars Produced by Field Scale Biomass Pyrolyzer

  • Jung, Won-K.
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.1
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    • pp.1-7
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    • 2011
  • Application of biochar to soils is proposed as a significant, long-term, sink for atmospheric carbon dioxide in terrestrial ecosystems. In addition to reducing emissions and increasing the sequestration of carbon, production of biochar and its application to soils will contribute improve soil quality and crop productivity. Objectives were i) to evaluate biochar productivity from crop residues using a low-cost field scale mobile pyrolyzer and ii) to evaluate characteristics of feedstocks and biochars from locally collected crop residues. Pyrolysis experiments were performed in a reactor operated at $400-500^{\circ}C$ for 3-4 hours using biomass samples of post-harvest residues of corn (Zea mays L.), cotton (Gossypium spp.), rice (Oryza sativa L.), sorghum (Sorghum bicolor L.) and wheat (Triticum aestivum L.). Feedstocks differed, but average conversion to biochar was 23%. Carbon content of biomass feedstock and biochar samples were 445 g $kg^{-1}$ and 597 g $kg^{-1}$, respectively. Total carbon content of biochar samples was 34% higher than its feedstock samples. Significant increases were found in P, K, Ca, Mg, and micro-nutrients contents between feedstock and biochar samples. Biochar from corn stems and rice hulls can sequester by 60% and 49% of the initial carbon input into biochar respectively when biochar is incorporated into the soils. Pyrolysis conversion of corn and rice residues sequestered significant amounts of carbon as biochar which has further environmental and production benefits when applied to soils. Field experiment with crop residue biochar will be investigated the stability of biochars to show long-term carbon sequestration and environmental influences to the cropping systems.

Automatic Evaluation of Elementary School English Writing Based on Recurrent Neural Network Language Model (순환 신경망 기반 언어 모델을 활용한 초등 영어 글쓰기 자동 평가)

  • Park, Youngki
    • Journal of The Korean Association of Information Education
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    • v.21 no.2
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    • pp.161-169
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    • 2017
  • We often use spellcheckers in order to correct the syntactic errors in our documents. However, these computer programs are not enough for elementary school students, because their sentences are not smooth even after correcting the syntactic errors in many cases. In this paper, we introduce an automated method for evaluating the smoothness of two synonymous sentences. This method uses a recurrent neural network to solve the problem of long-term dependencies and exploits subwords to cope with the rare word problem. We trained the recurrent neural network language model based on a monolingual corpus of about two million English sentences. In our experiments, the trained model successfully selected the more smooth sentences for all of nine types of test set. We expect that our approach will help in elementary school writing after being implemented as an application for smart devices.