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Quantification of Tc-99m-ethyl cysteinate dimer brain single photon emission computed tomography images using statistical probabilistic brain atlas in depressive end-stage renal disease patients:Correlation with disease severity and symptom factors

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Neural Regeneration Research 2012年第27期7卷 2151-2159页

作者： Heeyoung kim In joo kim Seong-Jang kim Sang Heon Song Kyoungjune Pak Keunyoung kim Department of Nuclear Medicine Pusan National University HospitalBusanRepublic of Korea Biomedical Research Institute Pusan NationalBusanRepublic of Korea Department of Internal Medicine Pusan National University HospitalBusanRepublic of Korea

This study adapted a statistical probabilistic anatomical map of the brain for single photon emission computed tomography images of depressive end-stage renal disease patients. This research aimed to investigate the relationship between symptom clusters, disease severity, and cerebral blood flow. Twenty-seven patients （16 males, 11 females） with stages 4 and 5 end-stage renal disease were enrolled, along with 25 healthy controls. All patients underwent depressive mood assessment and brain single photon emission computed tomography. The statistical probabilistic anatomical map images were used to calculate the brain single photon emission computed tomography counts. Asymmetric index was acquired and Pearson correlation analysis was performed to analyze the correlation between symptom factors, severity, and regional cerebral blood flow. The depression factors of the Hamilton Depression Rating Scale showed a negative correlation with cerebral blood flow in the left amygdale. The insomnia factor showed negative correlations with cerebral blood flow in the left amygdala, right superior frontal gyrus, right middle frontal gyrus, and left middle frontal gyrus. The anxiety factor showed a positive correlation with cerebral glucose metabolism in the cerebellar vermis and a negative correlation with cerebral glucose metabolism in the left globus pailidus, right inferior frontal gyrus, both temporal poles, and left parahippocampus. The overall depression severity （total scores of Hamilton Depression Rating Scale） was negatively correlated with the statistical probabilistic anatomical map results in the left amygdala and right inferior frontal gyrus. In conclusion, our results demonstrated that the disease severity and extent of cerebral blood flow quantified by a probabilistic brain atlas was related to various brain areas in terms of the overall severity and symptom factors in end-stage renal disease patients.

关键词： single photon emission computed tomography end-stage renal disease depression statisticalprobabilistic brain atlas disease severity cerebral blood flow symptom brain neural regeneration

Counter-balancing effects of Si on C partitioning and stacking fault energy of austenite in 10Mn quenching and partitioning steel

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Journal of Materials Science & Technology 2022年第3期98卷 248-257页

作者： Dong Hwi kim Jee-Hyun Kang Hojun Gwon joo Hyun Ryu Sung-joon kim Graduate Institute for Ferrous Technology Pohang University of Science and TechnologyPohang 37673Republic of Korea School of Materials Science and Engineering Institute of Materials TechnologyYeungnam UniversityGyeongsan 38541Republic of Korea POSCO Technical Research Laboratories POSCOGwangyang 57807Republic of Korea

Silicon is an essential alloying element in quenching and partitioning(Q&P)steels,because it is known to suppress carbide precipitation during partitioning step and promote carbon partitioning to stabilize *** 2 wt%Si was added to 10Mn-2Al-0.2C steel,the size and fraction of the carbides formed during partitioning became smaller than in the Si-free ***,the suppression of carbide formation promoted C partitioning into austenite as ***,austenite stability was always lower with Si under the equivalent partitioning condition because Si effectively decreased the stacking fault energy of *** partitioning progressed,the both yield and tensile strengths of the Si-added steel exceeded that of the Si-free steel with the similar ductility *** was because Si was an effective solid solution strengthener,and the austenite in the Si-added steel exhibited the appropriate stability to gradually transform into martensite throughout the *** resulting strengthening effect compensated for the softening caused by martensite ***,strain hardening rate decreased continuously throughout deformation,which resulted in high tensile strength and ductility.

关键词： Steels Q&P steel Silicon Austenite stability Tensile deformation Stacking fault energy Medium Mn steel

A new dimmer for alternating-current directly driven light-emitting-diode lamp

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Journal of Central South University 2012年第2期19卷 374-379页

作者： kim Jong-hyun RYU Myung-hyo YOON Hyok-min SONG eui-ho School of Mechatronics Changwon National University

A new dimmer using a mental-oxide-semiconductor field-effect transistor (MOSFET) for alternating-current (AC) directly driven light-emitting-diode (LED) lamp was presented. The control method of proposed dimmer is pulse width control (PWM) method. Compared with the conventional phase-controlled dimmer, the proposed PWM dimmer can produce sine wave and did not cause harmonics problem. Furthermore, the proposed control method did not amplify the light flicker due to the independence of input voltage. Therefore, the PWM dimmer can be used as the dimmer of the AC LED lamp instead of the conventional phase-controlled dimmer. The experimental result shows that the proposed PWM dimmer has good performances.

关键词： alternating-current directly driven light-emitting-diode pulse width control total harmonic distortion flicker triac

Historical Changes and Characteristics of Rehabilitation,Management and Utilization of Forest Resources in South Korea

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Journal of Mountain Science 2005年第2期2卷 164-172页

作者： eui-gyeong kim Dong-jun kim Division of Forest Science Gyeongsang National UniversityChinju 660-701KoreaSchool of Forest ResourcesChungbuk National UniversityCheongju 361-763Korea

This study analyzed the causes of forest devastation,the characteristics of forest rehabilitation process,and the success factors of reforestation. And it reviewed the management of rehabilitated forest resources and identified the income sources of mountain villages in South Korea. The devastation of forest starting from the early twentieth century was continued to the 1950’s. The main causes of deforestation were the illegal cutting of trees for fuel and the slash-and-burning agriculture in forest. The success factors of reforestation were the decrease in the dependence on forest of fuel source,strict administration system and national participation. Sustainable forest management could be made possible through the practical use of social issues like public work project for prevention of landslide damages caused by the thinned logs left in the forest. Also it could be possible by making people realize that the public benefit was obtained from forest and the income sources of mountain villages were supplemented by non-timber forest products and tourism. Food and Agriculture Organization indicated Korea as the country that forestation was succeeded in a very short period. Korea seems to be not ordinary because economic growth was accomplished with rehabilitating natural environment. Korean forestation can become a good prototype of combining environmental rehabilitation and economic development.

关键词： Forestation forest management forest utilization South Korea

Comparison of wrist motion classification methods using surface electromyogram

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Journal of Central South University 2013年第4期20卷 960-968页

作者： JEONG eui-chul kim Seo-jun SONG Young-rok LEE Sang-min Department of Electronic Engineering Inha University

The Gaussian mixture model (GMM), k-nearest neighbor (k-NN), quadratic discriminant analysis (QDA), and linear discriminant analysis (LDA) were compared to classify wrist motions using surface electromyogram (EMG). Effect of feature selection in EMG signal processing was also verified by comparing classification accuracy of each feature, and the enhancement of classification accuracy by normalization was confirmed. EMG signals were acquired from two electrodes placed on the forearm of twenty eight healthy subjects and used for recognition of wrist motion. Features were extracted from the obtained EMG signals in the time domain and were applied to classification methods. The difference absolute mean value (DAMV), difference absolute standard deviation value (DASDV), mean absolute value (MAV), root mean square (RMS) were used for composing 16 double features which were combined of two channels. In the classification methods, the highest accuracy of classification showed in the GMM. The most effective combination of classification method and double feature was (MAV, DAMV) of GMM and its classification accuracy was 96.85%. The results of normalization were better than those of non-normalization in GMM, k-NN, and LDA.

关键词： Gaussian mixture model k-nearest neighbor quadratic discriminant analysis linear discriminant analysis electromyogram (EMG) pattern classification feature extraction

Spilled gallstones mimicking a retroperitoneal sarcoma following laparoscopic cholecystectomy

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World Journal of Gastroenterology 2016年第17期22卷 4421-4426页

作者： Bum-Soo kim Sun-Hyung joo Hyun-Cheol kim Division of hepatobiliary surgery Department of Surgery Kyung Hee University Hospital at Gandong Kyung Hee University School of Medicine Seoul 134-727 South Korea

Laparoscopic cholecystectomy has become a standard treatment of symptomatic gallstone disease. Although spilled gallstones are considered harmless, unretrieved gallstones can result in intra-abdominal abscess. We report a case of abscess formation due to spilled gallstones after laparoscopic cholecystectomy mimicking a retroperitoneal sarcoma on radiologic imaging. A 59-year-old male with a surgical history of a laparoscopic cholecystectomy complicated by gallstones spillage presented with a 1 mo history of constant right-sided abdominal pain and tenderness. Computed tomography and magnetic resonance imaging demonstrated a retroperitoneal sarcoma at the sub-hepatic space. On open exploration a 5 cm × 5 cm retroperitoneal mass was excised. The mass contained purulent material and gallstones. Final pathology revealed abscess formation and foreign body granuloma. Vigilance concerning the possibility of lost gallstones during laparoscopic cholecystectomy is important. If possible, every spilled gallstone during surgery should be retrieved to prevent this rare complication.

关键词： Intra-abdominal abscess Spilled gallstone Laparoscopic cholecystectomy

A neural network model for high entropy alloy design

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npj Computational Materials 2023年第1期9卷 1734-1746页

作者： Jaemin Wang Hyeonseok Kwon Hyoung Seop kim Byeong-joo Lee Department of Materials Science and Engineering Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea Graduate Institute of Ferrous and Energy materials Technology(GIFT) Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea Center for Heterogenic Metal Additive Manufacturing Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea Institute for Convergence Research and Education in Advanced Technology Yonsei UniversitySeoul 03722Republic of Korea Advanced Institute for Materials Research(WPI-AIMR) Tohoku UniversitySendai 980-8577Japan

A neural network model is developed to search vast compositional space of high entropy alloys(HEAs).The model predicts the mechanical properties of HEAs better than several other ***’s because the special structure of the model helps the model understand the characteristics of constituent elements of *** addition,thermodynamics descriptors were utilized as input to the model so that the model predicts better by understanding the thermodynamic properties of HEAs.A conditional random search,which is good at finding local optimal values,was selected as the inverse predictor and designed two HEAs using the *** experimentally verified that the HEAs have the best combination of strength and ductility and this proves the validity of the model and alloy design *** strengthening mechanism of the designed HEAs is further discussed based on microstructure and lattice distortion *** present alloy design approach,specialized in finding multiple local optima,could help researchers design an infinite number of new alloys with interesting properties.

关键词： alloy alloys microstructure

Performance evaluation of the use of tire-derived fuel fly ash as mineral filler in hot mix asphalt concrete

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第2期7卷 249-258页

作者： Min Ju Choi Yong joo kim Hyeok Jung kim Jae Jun Lee BILTZONE Co. Ltd.Hwaseong 18514South Korea Korea Institute o f Civil Engineering and Building Technology Goyang-Si 10223South Korea Industry-Academic Cooperation Foundation Center Hankyong National UniversityAnseong-si 17579South Korea Department of Civil Engineering Chonbuk National UniversityJeonju 54896South Korea

According to deplete natural resources and need to protect the environment,the demand of a usage of waste material has significantly *** studies are currently being carried out on the development of innovative and environmentally friendly materials for securing the safety of road users and improving the performance and durability of *** example,studies are currently being conducted on the use of waste tires as a substitute for currently used *** the development of the automobile industry,the amount of waste tire has continuously increased in accordance with the increased vehicle ***-derived fuel(TDF)has been used as a fuel source with generated TDF fly *** filler,made of fine mineral particles of a physical size passing the number 200 standard mesh sieve(75 micron),plays an important role in asphalt mixtures *** paper presents an application of TDF fly ash as filler in hot mix asphalt(HMA).In this study,the performance of TDF fly ash was confirmed through a comparison with three other mineral fillers:stone dust,cement,and hydrated *** tests including Marshall stability test,moisture sensitivity test,dynamic immersion test,and a wheel tracking test were performed to investigate the difference in the behaviors of the samples with different parameters considered in this *** results show that the mechanical performance of hot mix asphalt using TDF fly ash satisfied the quality standard specification of the Ministry of Land,Infrastructure and Transport(MOLIT),*** can be concluded that the use of TDF fly ash as a mineral filler in HMA not only satisfied the mechanical properties,but also reduced the volume of the pollutants waste in the environment.

关键词： Asphalt mixture TDF fly ash Marshal stability Moisture sensitive TSR

Roughness coefficient and its uncertainty in gravel-bed river

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Water Science and Engineering 2010年第2期3卷 217-232页

作者： Ji-Sung kim Chan-joo LEE Won kim Yong-Jeon kim River and Coastal Research Division Korea Institute of Construction Technology

Manning＇s roughness coefficient was estimated for a gravel-bed river reach using field measurements of water level and discharge, and the applicability of various methods used for estimation of the roughness coefficient was evaluated. Results show that the roughness coefficient tends to decrease with increasing discharge and water depth, and over a certain range it appears to remain constant. Comparison of roughness coefficients calculated by field measurement data with those estimated by other methods shows that, although the field-measured values provide approximate roughness coefficients for relatively large discharge, there seems to be rather high uncertainty due to the difference in resultant values. For this reason, uncertainty related to the roughness coefficient was analyzed in terms of change in computed variables. On average, a 20% increase of the roughness coefficient causes a 7% increase in the water depth and an 8% decrease in velocity, but there may be about a 15% increase in the water depth and an equivalent decrease in velocity for certain cross-sections in the study reach. Finally, the validity of estimated roughness coefficient based on field measurements was examined. A 10% error in discharge measurement may lead to more than 10% uncertainty in roughness coefficient estimation, but corresponding uncertainty in computed water depth and velocity is reduced to approximately 5%. Conversely, the necessity for roughness coefficient estimation by field measurement is confirmed.

关键词： roughness coefficient estimation field measurement gravel-bed river uncertainty