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A single injection of saphenous nerve block reduces postoperative bleeding after total knee arthroplasty (무릎전치환술 환자에서 일회성 복재신경차단술이 수술 후 출혈량 감소에 미치는 영향)

  • Choi, Yun Suk;Yun, So Hui;Cho, Seung Yeon;Song, Seung Eun;Kim, Sang Rim
    • Journal of Medicine and Life Science
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    • v.18 no.1
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    • pp.11-15
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    • 2021
  • In elderly patients, the vital parameters tend to fluctuate based on the blood volume status, which may cause sudden hypovolemic shock if the postoperative bleeding continues. Particularly, those who undergo surgery for arthritis needs to pay extra attention because the bleeding may persist over the joints after the surgery. Therefore, appropriate pain control is required to reduce the postoperative blood loss. This retrospective chart review study was conducted to assess the postoperative pain control and reduction of blood loss with a single injection of saphenous nerve block (SNB) in elderly patients with osteoarthritis. We reviewed the electronic medical records of patients who underwent knee total arthroplasty with spinal anesthesia between January and May 2016. A total of 51 patients participated in this study. All patients were treated with intravenous patient-controlled analgesia for the postoperative pain control, and additional analgesic agents were administered at a visual analogue scale above a score of 6. In 25 patients, SNB was performed using ultrasound with the administration of 0.75% ropivacaine (15 mL) after the surgery. Patients who received additional analgesics were significantly low in the nerve block group (P=0.009). Additionally, the volume of blood loss from catheter drainage was significantly low at 2 and 3 days postoperatively (P=0.013 and P=0.041, respectively) in the nerve block group. In patients who underwent total knee arthroplasty with osteoarthritis, only a single injection of saphenous nerve block was sufficient for the postoperative pain control and reduced bleeding.

Design of Low-loss Microstrip-to-Waveguide Inline Transition Structure (저손실 마이크로스트립-도파관 inline 전이구조 설계 )

  • Young-Gon Kim;Han-Chun Ryu;Se-Hoon Kwon;Seon-Keol Woo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.23 no.4
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    • pp.29-34
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    • 2023
  • A clear and efficient design method for a microstrip-to-waveguide inline transition, which is based on an analytical model, is presented. The transition consists of three parts: a microstrip-to-SIW transition, a dielectric-loaded waveguide with substrate-height, and a stepped-height waveguide. The shape of the transitional structure is formed for impedance matching. Two equivalent type0s of dielectric-loaded transitional structures are proposed. The design method is applicable to any size of the waveguide, but a design method of two Ka-band transitions is demonstrated. The proposed transitions, in a back-to-back configuration, have less than 1.2 dB insertion loss and more than 15 dB return loss from 29.8 GHz to 38.2 GHz.

F_MixBERT: Sentiment Analysis Model using Focal Loss for Imbalanced E-commerce Reviews

  • Fengqian Pang;Xi Chen;Letong Li;Xin Xu;Zhiqiang Xing
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.2
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    • pp.263-283
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    • 2024
  • Users' comments after online shopping are critical to product reputation and business improvement. These comments, sometimes known as e-commerce reviews, influence other customers' purchasing decisions. To confront large amounts of e-commerce reviews, automatic analysis based on machine learning and deep learning draws more and more attention. A core task therein is sentiment analysis. However, the e-commerce reviews exhibit the following characteristics: (1) inconsistency between comment content and the star rating; (2) a large number of unlabeled data, i.e., comments without a star rating, and (3) the data imbalance caused by the sparse negative comments. This paper employs Bidirectional Encoder Representation from Transformers (BERT), one of the best natural language processing models, as the base model. According to the above data characteristics, we propose the F_MixBERT framework, to more effectively use inconsistently low-quality and unlabeled data and resolve the problem of data imbalance. In the framework, the proposed MixBERT incorporates the MixMatch approach into BERT's high-dimensional vectors to train the unlabeled and low-quality data with generated pseudo labels. Meanwhile, data imbalance is resolved by Focal loss, which penalizes the contribution of large-scale data and easily-identifiable data to total loss. Comparative experiments demonstrate that the proposed framework outperforms BERT and MixBERT for sentiment analysis of e-commerce comments.

Study for Conductive and Non-conductive Multi-layers Depth Profiling Analysis of Radio Frequency Gas-jet Boosted Glow Discharge Spectrometry (Modified Gas-jet Boosted Radio-frequency Glow Discharge 셀의 개발 및 최적화에 관한 연구)

  • Cho, Won Bo;Borden, Stuart;Jeong, Jong Pil;Kang, Won Kyu;Kim, Kyu Whan;Kim, Hyo Jin
    • Analytical Science and Technology
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    • v.15 no.2
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    • pp.108-114
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    • 2002
  • The new system using a glow discharge atomic emission spectrometer for the direct analysis of solid samples has been developed and characterized. The system was consisted of new glow discharge cell improved previous gas-jet boosted nozzle and radio-frequency power supply. In the case of previous type glow discharge chamber, it had been fitted trace analysis of low alloy steel with low discharge power, because it was to decrease redeposition and increase sample weight loss. But it had a problem that plasma becomes unstale due to increased sample weight loss and redeposition resulting from the high discharge power. Because of being problem of previous glow discharge, it is impossible to analyze using high power. The modified gas-jet boosted glow discharge to solve this problem would improve to be less sample loss rate of modified nozzle than sample loss rate of previous nozzle on the equal discharge condition, and improve to increase stability of plasma. The effect of discharge parameters such as discharge pressure, gas flow rate and power on the sample loss rate, emission intensity has been studied to find optimum discharge conditions. The calibration curves of Fe were obtained with 3 low-alloy samples.

Low serum 25-hydroxyvitamin D levels, tooth loss, and the prevalence of severe periodontitis in Koreans aged 50 years and older

  • Kim, Hyunju;Shin, Min-Ho;Yoon, Suk-Ja;Kweon, Sun-Seog;Lee, Young-Hoon;Choi, Chang-Kyun;Kim, OkJoon;Kim, Young-Joon;Chung, HyunJu;Kim, Ok-Su
    • Journal of Periodontal and Implant Science
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    • v.50 no.6
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    • pp.368-378
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    • 2020
  • Purpose: Vitamin D deficiency may cause bone loss and increased inflammation, which are well-known symptoms of periodontal disease. This study investigated whether serum 25-hydroxyvitamin D (25(OH)D) levels are associated with periodontal disease status and tooth loss. Methods: Cross-sectional data from 5,405 individuals aged ≥50 years (2,253 males and 3,152 females) were obtained from the 2008-2010 Dong-gu study, a prospective cohort study of risk factors for chronic diseases. Periodontal examinations were conducted to evaluate the number of remaining teeth, the periodontal probing depth (PPD), the clinical attachment level (CAL), and bleeding on probing. The percentages of sites with PPD ≥4 mm and CAL ≥4 mm were recorded for each participant. The severity of periodontitis was classified using the Centers for Disease Control and Prevention and the American Academy of Periodontology case definitions. Serum 25(OH)D levels were classified as reflecting severe deficiency, deficiency, insufficiency, or sufficiency. Multivariate linear regression analysis was performed to assess the associations of serum 25(OH)D levels with periodontal parameters and the number of remaining teeth after adjusting for confounders including age, smoking status, alcohol consumption status, month of blood collection, and physical activity. Multivariate logistic regression was used to evaluate the association between serum vitamin D levels and severe periodontitis. An overall statistical analysis and a stratified analysis by sex were performed. Results: Overall, the rates of severe deficiency, deficiency, insufficiency, and sufficiency were 6.5%, 67.9%, 22.4%, and 3.2%, respectively. After adjustment for confounders, vitamin D levels were directly associated with the number of remaining teeth, an association that was significant in males, but not in females. Sufficient serum 25(OH)D was associated with a low frequency of severe periodontitis. Conclusions: This population-based cross-sectional study indicates that low serum 25(OH) D is significantly associated with tooth loss and severe periodontitis in Koreans aged 50 years and older.

The 4:1(50-Ω:12.5-Ω) microstrip-slot line impedance transformer using a dielectric resonator (유전체 공진기를 이용한 4:1(50-Ω:12.5-Ω) 마이크로스트립-슬롯 선로 임피던스 변환기)

  • Park, Ung-hee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.11
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    • pp.1484-1491
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    • 2020
  • Since the slot line transmits electric and magnetic signals through the slot, the size of the slot greatly affects the signal power loss. In order to have low loss, the slot line is mainly used at a high frequency of above 3GHz on a substrate having a high dielectric constant(er). This paper proposes the 4:1 impedance transformer using a slot line on TLC-30 laminate (h=20mil, er=3.0; Taconic) being a relatively low dielectric constant at a frequency of 1.85GHz. In the proposed impedance transformer, the dielectric resonator is arranged on the slot line to reduce signal loss occurring at the slot line. The proposed 4:1 microstrip-slot line impedance transformer fabricated using a (Zr,Sn)TiO4 dielectric resonator(er=38) has the transmission loss(S21) of -0.375dB and the reflection value(S11) of -27.6dB at 1.855GHz. This confirms that the slot line can be stably used even in a low dielectric constant substrate and a low frequency region by using a dielectric resonator.

Auditory brainstem response (ABR) results in NICU graduates (신생아 집중치료실 퇴원아의 청성뇌간반응(ABR) 결과에 미치는 위험인자 및 경과)

  • Choi, Hee-Joung;Lee, Tae-ho;Oh, Ki-Won;Kim, Heng-Mi
    • Clinical and Experimental Pediatrics
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    • v.49 no.12
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    • pp.1301-1307
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    • 2006
  • Purpose : Hearing loss is one of the most common birth defects, and early detection and intervention positively impact language/speech and cognitive development. It has been reported that NICU graduates have a high incidence of hearing loss. So we investigated the incidence, risk factors and clinical outcome of hearing loss in NICU graduates. Methods : This study involved neonatal auditory brainstem response (ABR) testing of newborn infants who graduated from the NICU of Kyungpook National University Hospital during a 3-year period (between July 2002 and June 2005) and subsequent follow-up of these infants. Results : ABR evaluations were performed on 474 infants. Of these infants, 64 showed abnormal ABR (13.5 percent). Of 128 ears from these 64 infants, two ears (1.6 percent) and 10 ears (7.8 percent) were classified as severe and profound hearing loss, respectively. The infants with abnormal ABR had higher incidence of prematurity, low birth weight, very low birth weight, neonatal asphyxia, cranio-facial malformation and amikacin treatment over 15 days (P<0.05). In infants with hyperbilirubinemia, the peak level of serum bilirubin, duration of phototherapy and exchange transfusion were not associated with the higher incidence of hearing loss. Follow-up ABR evaluation was performed on 15 infants with abnormal ABR at $8.8{\pm}4.4months$. In follow-up ABR, 80.0% showed improvement or normalization of threshold sensitivity. Conclusion : NICU graduates exhibit high risk for hearing loss. Systemic and effective hearing assessment program is needed for these high risk infants.

The Correlations of Walking Exercise Program-Induced Abdominal Visceral Fat Loss with Metabolic Syndrome Risk Factors (걷기운동 프로그램에 의한 복부 내장지방의 감량과 대사증후군 위험인자 간의 관련성)

  • Kim, Myoung-Su;Kim, Sung-Hee;Lee, Shin-Ho
    • Journal of Digital Convergence
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    • v.14 no.11
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    • pp.589-596
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    • 2016
  • The purpose of current study was to investigate the correlations of walking exercise program-induced abdominal visceral fat loss with metabolic syndrome risk factors in middle-aged women. The walking exercise program was provided at a frequency of 3 sessions, respectively, per week for a duration of 12 weeks. Then, the subjects were classified into either those whose abdominal visceral fat loss belonged to low 25 percentile (low 25% group, n=8) or those whose abdominal visceral fat loss belonged to high 25 percentile(high 25% group, n=8) based on the amount of abdominal visceral fat loss induced by the walking exercise. Metabolic syndrome risk factors(waist circumference, triglycerides, HDL-cholesterol, fasting blood glucose, blood pressure) between groups according to the 12 weekly walking exercise program had no difference. In conclusion, the findings of the present study show that the walking exercise-induced total abdominal fat and visceral fat loss were positively relate to waist and blood pressure(SBP, DBP) and that the walking exercise-induced subcutaneous fat loss were positively relate to waist and blood pressure(SBP).

Studies on the Relative Durability of Useful Woods Grown in Korea to the Parasitic Wood Destroying Fungi (목재부후균의(木材腐朽菌)의 기생(寄生)에 의한 한국산(韓國産) 유용목재(有用木材)의 비교내후성(比較耐朽性) 연구(硏究))

  • Chung, Dae-Kyo
    • Journal of the Korean Wood Science and Technology
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    • v.15 no.2
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    • pp.1-15
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    • 1987
  • This experiment was undertaken for the purpose of investigation of relative durability about thirty sorts of the korean native wood and nine sorts of the wood destroying fungi Polystictus versicolor, Irpex consors. Poria vaporaria, Merulius lacrymans, Schizophyllum commune, Trametes pini, Lenzites betulina, Paxillus panuoides by means of a laboratory methods. The results obtained are; (from the table 2 to 10) 1. By measuring the percentage of loss in weight with regard to Polystictus versicolor, the sap wood contained in Junipeus chinesis was calculated at 18.2%, therefore it is much higher durability than any others and the sap wood contained in Pinus densiflora was measured at 44.10%, therefore it is much lower durability than any others. 2. By measuring the percentage of loss in weight with regard to Irpex consors, the heart wood contained in Butula schmidtii was calculated at 1.23%, therefore durability is very high and the heart wood contained in Quercus dentata was calculated at 26.79%, therefore durability is very low. 3. By measuring the percentage of lass in weight with regard to Lenzites betulina, the heart wood contained in Betula schmidtii was calculated at 5.33%, therefore it is much higher durability than any others and the sap wood with regard to Abies holophylla was measured at 45.48%, therefore durability is very low. 4. By measuring the percentage of loss in weight with regard to Poria vaporaria, the sap wood contained in Fraxinus rhynchophylla was calculated at 5.57%, therefore durability is very high and the sap wood contained in Paulownia coreana was calculated at 35.6%, therefore it is much lower durability than any others. 5. By measuring the percentage of loss in weight with regard to Merulius lacrymans, the heart wood contained in Castanea crenata was measured at 0.09% and in the next place, the heart wood contained in Abies holophylla calculated at 0.15% did not decay almost and the sap wood contained in Cornus controversa was measured at 32.88%, therefore it is lower durability than any others. 6. By measuring the percentage of loss in weight with regard to Schizophyllum commune, the sap wood cantained in Junipensis chinensis was calculated at 1.09%, therefore durability is very high and the sap wood contained in Populus deltoides was calculated at 36.87%, it is much lower durability than any others. 7. By measuring the percentage of loss ill weight with regard to Trametes pini, the sap wood contained in Robinia pseudo-acacia was calculated at 1.33%, therefore durability is very high and the sap wood contained in Comus controversa was calculated at 33.19%, it is much lower durability than any others. 8. By measuring the percentage of loss ill weight with regard to Paxillus panuoides. the heart wood contained in Zelkova serrata was calculated at 1.73%, therefore durability is very high and the sap wood contained in Populus deltoides was calculated at 42.30%, therefore durability in very low. 9. By measuring the percentage of loss in weight with regard to Dardalea quercina, the heart wood contained in Castanea crenata was calculated at 0.92%, therefore durability is very high and the sap wood contained in Cornus controversa was calculated at 32.00% therefore durability is very low. The above results are summarized as follows 1. Durability between the heart wood and the soft wood find that it is nonsignificant, while durability is higher heart wood than sap wood. 2. Special sorts including in the element like Castanea cenata, Robinia pseudo-acacia, Juniperus chinensis and heart wood like Betula schmiditii and Styrax obasia are highly durable and soft wood like Cornus controversa, Populus davidiana, Salix koreensis, Celtis jessensis are lowly durable in general. 3. Among the wood destroying fungi Paxillus panuoides is highly durable and as follows. Poria vaporaria, Lenzites betulina and the Daedalea quercina is less in general and Irpex consors, Mersulius lacrymans are a middle degree.

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Mass Transfer of Aerosol onto Spherical Collector at Low Knudsen Number (저 누드센 영역에서 구형 포집체상의 에어로졸 물질 전달)

  • Jung, Chang-Hoon
    • Journal of Korean Society for Atmospheric Environment
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    • v.21 no.5
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    • pp.547-555
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    • 2005
  • In this study, an analytical expression for aerosol mass transfer at spherical collector in the low Knudsen number region was obtained. Happel's zero shear stress cell model was extended in the low Knudsen number region and the result was compared with numerical solution results. The zero vorticity model based on the Kuwabara's cell model was also extended in the low Knudsen number region and compared with Happel's results. The results showed that both analytic and numerical solution agree very well with each other in low Knudsen number region. Happel's zero shear stress model also agrees with Kuwabara's zero vorticity model without significant loss of accuracy. The obtained solution converges to the original solution of Lee et al. (1999) when Knudsen number approaches to zero. Subsequently, this study derived most general type of analytic solution for aerosol mass transfer of spherical collector including the finite Knudsen number region.