• Title/Summary/Keyword: Resonance

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Risk Factors for the Treatment Failure of Antibiotic-Loaded Cement Spacer Insertion in Diabetic Foot Infection (당뇨병성 족부 감염에서 항생제 혼합 시멘트 충전물 사용의 치료 실패 위험 인자 분석)

  • Park, Se-Jin;Song, Seungcheol
    • Journal of Korean Foot and Ankle Society
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    • v.23 no.2
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    • pp.58-66
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    • 2019
  • Purpose: To evaluate the efficacy of antibiotic-loaded cement spacers (ALCSs) for the treatment of diabetic foot infections with osteomyelitis as a salvage procedure and to analyze the risk factors of treatment failure. Materials and Methods: This study reviewed retrospectively 39 cases of diabetic foot infections with osteomyelitis who underwent surgical treatment from 2009 to 2017. The mean age and follow-up period were $62{\pm}13years$ and $19.2{\pm}23.3months$, respectively. Wounds were graded using the Wagner and Strauss classification. X-ray, magnetic resonance imaging (or bone scan) and deep tissue cultures were taken preoperatively to diagnose osteomyelitis. The ankle-brachial index, toe-brachial index (TBI), and current perception threshold were checked. Lower extremity angiography was performed and if necessary, percutaneous transluminal angioplasty was conducted preoperatively. As a surgical treatment, meticulous debridement, bone curettage, and ALCS placement were employed in all cases. Between six and eight weeks after surgery, ALCS removal and autogenous iliac bone graft were performed. The treatment was considered successful if the wounds had healed completely within three months without signs of infection and no additional amputation within six months. Results: The treatment success rate was 82.1% (n=32); 12.8% (n=5) required additional amputation and 5.1% (n=2) showed delayed wound healing. Bacterial growth was confirmed in 82.1% (n=32) with methicillin-resistant Staphylococcus aureus being the most commonly identified strain (23.1%, n=9). The lesions were divided anatomically into four groups; the largest number was the toes: (1) toes (41.0%, n=16), (2) metatarsals (35.9%, n=14), (3) midfoot (5.1%, n=2), and (4) hindfoot (17.9%, n=7). A significant difference in the Strauss wound score and TBI was observed between the treatment success group and failure group. Conclusion: The insertion of ALCSs can be a useful treatment option in diabetic foot infections with osteomyelitis. Low scores in the Strauss classification and low TBI are risk factors of treatment failure.

Design of Miniaturization Terminal Antenna for 2.4 GHz WiFi Band with MZR (MZR을 이용한 2.4 GHz WiFi 대역 소형 단말기 안테나 설계)

  • Lee, Young-Hun
    • Journal of IKEEE
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    • v.23 no.1
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    • pp.14-21
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    • 2019
  • In this paper, we implemented an on-board miniaturization antenna operating 2.4 GHz using MZR(Mu Zero Resonator). It is must be operating under the constraint that the size of the small terminal PCB should be $78{\times}38{\times}0.8mm^3$ and the size of the system should be $63{\times}38{\times}0.8mm^3$ and the size of the radiating part should be $15{\times}38{\times}0.8mm^3$. The feeding structure uses a CPW structure for stable feeding and a feeding point at the upper left of the system board. A magnetic field coupling structure is used for coupling the feeding part and the antenna. The resonance frequency of the MZR is determined by the series inductance and capacitance of the cell, so the gap between the cells, the length of the cell, the length of the interdigital capacitor, and the spacing between the radiation part and the ground plane are analyzed. The antenna was designed and fabricated using the results. The total size of the antenna including the feed structure is $20.8{\times}9.0{\times}0.8mm^3$, and the electrical length is $0.1664{\lambda}_0{\times}0.072{\lambda}_0{\times}0.0064{\lambda}_0$. The measurement result for 10 dB bandwidth, gain and directivity are 440 MHz(18.3%), 0.4405 dB, and 2.722 dB respectively. It is confirmed that the radiation pattern has omnidirectional characteristics and it can be applied to ultra small terminal antenna.

Personal Credit Evaluation System through Telephone Voice Analysis: By Support Vector Machine

  • Park, Hyungwoo
    • Journal of Internet Computing and Services
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    • v.19 no.6
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    • pp.63-72
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    • 2018
  • The human voice is one of the easiest methods for the information transmission between human beings. The characteristics of voice can vary from person to person and include the speed of speech, the form and function of the vocal organ, the pitch tone, speech habits, and gender. The human voice is a key element of human communication. In the days of the Fourth Industrial Revolution, voices are also a major means of communication between humans and humans, between humans and machines, machines and machines. And for that reason, people are trying to communicate their intentions to others clearly. And in the process, it contains various additional information along with the linguistic information. The Information such as emotional status, health status, part of trust, presence of a lie, change due to drinking, etc. These linguistic and non-linguistic information can be used as a device for evaluating the individual's credit worthiness by appearing in various parameters through voice analysis. Especially, it can be obtained by analyzing the relationship between the characteristics of the fundamental frequency(basic tonality) of the vocal cords, and the characteristics of the resonance frequency of the vocal track.In the previous research, the necessity of various methods of credit evaluation and the characteristic change of the voice according to the change of credit status were studied. In this study, we propose a personal credit discriminator by machine learning through parameters extracted through voice.

3-Dimensional Numerical Analysis of Air Flow inside OWC Type WEC Equipped with Channel of Seawater Exchange and Wave Characteristics around Its Structure (in Case of Regular Waves) (해수소통구를 구비한 진동수주형 파력발전구조물 내에서 공기흐름과 구조물 주변에서 파랑특성에 관한 3차원수치해석(규칙파의 경우))

  • Lee, Kwang Ho;Lee, Jun Hyeong;Jeong, Ik Han;Kim, Do Sam
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.30 no.6
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    • pp.242-252
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    • 2018
  • It is well known that an Oscillating Water Column Wave Energy Converter (OWC-WEC) is one of the most efficient wave absorber equipment. This device transforms the vertical motion of water column in the air chamber into the air flow velocity and produces electricity from the driving force of turbine as represented by the Wells turbine. Therefore, in order to obtain high electric energy, it is necessary to amplify the water surface vibration by inducing resonance of the piston mode in the water surface fluctuation in the air chamber. In this study, a new type of OWC-WEC with a seawater channel is used, and the wave deformation by the structure, water surface fluctuation in the air chamber, air outflow velocity from the nozzle and seawater flow velocity in the seawater channel are evaluated by numerical analysis in detail. The numerical analysis model uses open CFD code OLAFLOW model based on multi-phase analysis technique of Navier-Stokes solver. To validate model, numerical results and existing experimental results are compared and discussed. It is revealed within the scope of this study that the air flow velocity at nozzle increases as the Ursell number becomes larger, and the air velocity that flows out from the inside of the air chamber is larger than the velocity of incoming air into the air chamber.

Cyclofarnesane sesquiterpene glucoside from the whole plant of Loranthus tanakae and its cytotoxicity ('꼬리겨우살이'(Loranthus tanakae) 전초로부터 cyclofarnesane sesquiterpene glucoside의 분리 동정 및 세포독성)

  • Joo, Sun-Woo;Kim, Hyoung-Geun;Oh, Eun-Ji;Ko, Jung-Hwan;Lee, Yeong-Geun;Kang, Se-Chan;Lee, Dae Young;Baek, Nam-In
    • Journal of Applied Biological Chemistry
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    • v.62 no.1
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    • pp.7-10
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    • 2019
  • The whole plants of Loranthus tanakae were repeatedly extracted with 80% aqueous MeOH and the concentrate was partitioned into ethyl acetate (EtOAc), n-butyl alcohol (n-BuOH) and $H_2O$ fractions. The repeated silica gel ($SiO_2$), octadecyl $SiO_2$ (ODS), and Sephadex LH-20 column chromatographies for the n-BuOH fraction led to isolation of a cyclofarnesane sesquiterpene glucoside. The chemical structure including stereo structure was determined to be a (1'R,3'S,5'R,8'S,2E,4E)-dihydrophaseic acid $3^{\prime}-O-{\beta}-{\text\tiny{D}}$-glucopyranoside on the basis of spectroscopic analyses. This compound was isolated for the first time from L. tanakae in this study. Compound 1 showed a moderate dose-dependent cytotoxicity against human Caucasian gastric adenocarcinoma cells and human hepatocyte cari-noma cells cell lines at higher than $50{\mu}g/mL$.

Evaluation of Image Usability by SEMAC Turbo Factor Change using Susceptibility Artifact Reduction (Susceptibility Artifact를 감소시키는 SEMAC 사용 시 Turbo Factor 변화에 따른 영상의 유용성 평가)

  • Choi, Young-Jae;Kim, Sang-Hyun
    • Journal of the Korean Society of Radiology
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    • v.13 no.1
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    • pp.31-37
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    • 2019
  • The study analyzes Non SEMAC and SEMAC to reduce susceptibility artifacts that may occur when performing magnetic resonance imaging(MRI) of metal patients. The Foot and Ankle Phantom was used as the experimental tool and the 3.8 cm general screw was used to make the magnetic susceptibility artifact. The experimental equipment was used 3.0T Magnetom Skyra and the area was measured with the 17th image where the signal off is the most noticeable in the obtained image. Statistical analysis was performed using the SPSS(Ver.25) program and the significance was assessed by the Wilcoxon Signed Rank Test. As a result, the area of Non SEMAC which is the lowest signal was $289.53{\pm}23.07197mm$. When the Turbo Factor was changed to 3, 4, and 5 after SEMAC use, it decreased to $125.02{\pm}7.45875mm$, $120.96{\pm}12.01704mm$ and $108.79{\pm}16.53498mm$, respectively. In conclusion, this study demonstrates that Using SEMAC with Turbo Factor effectively reduces the susceptibility artifacts.

Seismic Performance Evaluation of the Li-Polymer Battery Rack System for Nuclear Power Plant (원자력발전소용 리튬폴리머 배터리 랙 시스템의 내진성능평가)

  • Kim, Si-Jun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.5
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    • pp.13-19
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    • 2019
  • After the Fukushima nuclear accident, a new power supply using a lithium polymer battery has been proposed the first time in the world as the safety of the emergency battery facility has been required. It is required to have the safety of the rack system in which the battery device is installed in order to apply the proposed technology to the field. Therefore, the purpose of this study is to evaluate the seismic performance of string and rack frame for lithium-polymer battery devices developed for the first time in the world to satisfy 72 hours capacity. (1) The natural frequency of the unit rack system was 9 Hz, and the natural frequency before and after the earthquake load did not change. This means that the connection between members is secured against the design earthquake load. (2) he vibration reduction effect by string design was about 20%. (3) As a result of the seismic performance test under OBE and SSE conditions, the rack frame system was confirmed to be safe. Therefore, the proposed rack system can be applied to the nuclear power plant because the rack system has been verified structural safety to the required seismic forces.

Quantitative Feasibility Evaluation of 11C-Methionine Positron Emission Tomography Images in Gamma Knife Radiosurgery : Phantom-Based Study and Clinical Application

  • Lim, Sa-Hoe;Jung, Tae-Young;Jung, Shin;Kim, In-Young;Moon, Kyung-Sub;Kwon, Seong-Young;Jang, Woo-Youl
    • Journal of Korean Neurosurgical Society
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    • v.62 no.4
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    • pp.476-486
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    • 2019
  • Objective : The functional information of $^{11}C$-methionine positron emission tomography (MET-PET) images can be applied for Gamma knife radiosurgery (GKR) and its image quality may affect defining the tumor. This study conducted the phantom-based evaluation for geometric accuracy and functional characteristic of diagnostic MET-PET image co-registered with stereotactic image in Leksell $GammaPlan^{(R)}$ (LGP) and also investigated clinical application of these images in metastatic brain tumors. Methods : Two types of cylindrical acrylic phantoms fabricated in-house were used for this study : the phantom with an array-shaped axial rod insert and the phantom with different sized tube indicators. The phantoms were mounted on the stereotactic frame and scanned using computed tomography (CT), magnetic resonance imaging (MRI), and PET system. Three-dimensional coordinate values on co-registered MET-PET images were compared with those on stereotactic CT image in LGP. MET uptake values of different sized indicators inside phantom were evaluated. We also evaluated the CT and MRI co-registered stereotactic MET-PET images with MR-enhancing volume and PET-metabolic tumor volume (MTV) in 14 metastatic brain tumors. Results : Imaging distortion of MET-PET was maintained stable at less than approximately 3% on mean value. There was no statistical difference in the geometric accuracy according to co-registered reference stereotactic images. In functional characteristic study for MET-PET image, the indicator on the lateral side of the phantom exhibited higher uptake than that on the medial side. This effect decreased as the size of the object increased. In 14 metastatic tumors, the median matching percentage between MR-enhancing volume and PET-MTV was 36.8% on PET/MR fusion images and 39.9% on PET/CT fusion images. Conclusion : The geometric accuracy of the diagnostic MET-PET co-registered with stereotactic MR in LGP is acceptable on phantom-based study. However, the MET-PET images could the limitations in providing exact stereotactic information in clinical study.

Structural Analysis of Volatile Matters and Heavy Oil Fractions from Pyrolysis Fuel Oil by the Heat Treatment Temperature (열처리 온도에 따른 열분해 연료유 내 휘발유분 및 잔류 중질유분의 구조 분석)

  • An, Donghae;Kim, Kyung Hoon;Kim, Jong Gu;Lee, Young-Seak
    • Applied Chemistry for Engineering
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    • v.30 no.3
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    • pp.297-302
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    • 2019
  • In order to investigate structural changes of the pyrolysis fuel oil (PFO), the volatile matters and heavy oil fractions were separated from PFO by heat treatment temperature. As a result of $^1H-NMR$ analysis of volatile matters, 1~2 ring aromatic compounds contained in the petroleum residue were mostly removed at a temperature before $340^{\circ}C$. Moreover, new peaks corresponding to aliphatic hydrocarbons were detected at the chemical shift of 2.0~2.4 ppm. It is attributed that the aliphatic hydrocarbon sidechain was cracked from the aromatic compound by the cracking reaction occurred at $320^{\circ}C$. The C/H mole ratio and aromaticity increased with increasing the heat treatment temperature. Therefore, from the structural analysis results of heavy oil fractions and volatile matters from PFO, the decomposition of the aliphatic sidechain by cracking reaction and the separation of volatile matters by boiling point of components were mostly affected structure changes of the PFO.

Comparison of Volatile Fatty Acids, Monosaccharide Analysis and Metabolic Profiling in Rumen Fluid According to Feeding Methods (사료 급여 방식에 따른 반추위액 내 휘발성지방산과 단당류 비교 분석과 대사산물 분석)

  • Eom, Jun-Sik;Lee, Shin-Ja;Lee, Yoo-Gyung;Lee, Sung-Sill
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.12
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    • pp.814-824
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    • 2018
  • This study was conducted to investigate VFA, monosaccharides and metabolites in rumen fluid according to feeding methods. Three castrated Hanwoo steers were used to the $3{\times}3$ Latin square design, 10 day for the diet adaptation period. VFA and monosaccharides which were not detected by HPLC and HPAEC however, those were detected by $^1H-NMR$. Among the metabolites measured by $^1H-NMR$ carbohydrate metabolites, pyruvate was detected only in the rumen fluid before feeding and succinate was detected before and after feeding rumen fluid. In amino acid total 9 metabolites were detected. In lipid metabolites, ethylene glycol was significantly higher (P<0.05) in before feeding Con group. In aliphatic acylic metabolite, trimethylamine N-oxide was no significant difference observed compare to Con group. In this study, many metabolites were observed in the rumen fluid by $^1H-NMR$, and it confirmed that rumen metabolic products were changed by feeding methods.