Effect of Modified High-heels on Metatarsal Stress in Female Workers

Kim, Kwantae,Peng, Hsien-Te Korean Society of Sport Biomechanics 2019 한국운동역학회지 Vol.29 No.3

Objective: The purpose of this study was to identify the effect of high-heels (HH) modification on metatarsal stress in female workers. Method: Seven females who work in clothing stores ($heights=160.4{\pm}3.9cm$; $weights=47.4{\pm}4.1kg$; $age=31.3{\pm}11.1yrs$; $HH\;wear\;career=8{\pm}6.5yrs$) wore two types of HH (original and modified). The modified HH had been grooved with 1.5 cm radius and 0.2 cm depth around the first metatarsal area inside of the shoes using the modified shoe-last. Participants were asked to walk for 15 minutes on a treadmill and to stand for 10 minutes with original and modified HH, respectively. Kinetics data were collected by the F-scan in-shoe system. After each test, participants were asked to rate their perceived exertion using the Borg's 15-grade RPE scale and interviewed about their feeling of HH. Nonparametric Wilcoxon signed-rank test and effect size (Cohen's d) were used to determine the difference of the variables of interest between the original and modified HH. Results: In the present study, modified HH of the peak contact pressure of 1st metatarsal (PCP) left, PCP right, pressure time integral (PTI) left, peak pressure gradient (PPG) left during standing and PPG right during walking are greater than original HH. And even it didn't show statistically significant, the average in all pressure values of modified HH showed bigger than original HH. It surmised to be related to awkward with modified HH. Even though they said to feel the comfortable cause of big space inside of HH in the interview, they seemed to be not enough time to adapt with new HH. So their walking and standing postures were unstable. Conclusion: Modified the fore-medial part of HH can reduce the stress in the first metatarsal head and big toe area during standing and walking.

Effects of Modified Insole on Lower Extremities Biomechanics in College Male Basketball Players

( Kwantae Kim ),( Mi-sun Kim ),( Ki-kwang Lee ),( Hsien-te Peng ) 한국체육학회 2020 International journal of human movement science Vol.14 No.1

The purpose of this study was to investigate the effect of fore-medial-side thin insole on lower extremities kinematics and kinetics in college male basketball players. Seven male college basketball players voluntarily participated in the study (heights= 173.1 ± 3.1 cm; weights= 68.6 ± 5.7 kg; age= 21.1 ± 2.0 yrs.). They wore the same basketball shoes with 2 types of insoles: one type was original insole (OI); another one was fore-medial-side gradually thin insole (TI). Participants were asked to perform L-cut, V-cut, Backdoor-cut, walk, shuttle run of basketball movement in a 5-meter running way with their maximum speed. They were instructed to step with their right leg when they changed direction. The kinematic and kinetic data were collected during support phase. Non-parametric Wilcoxon signed rank test and the effect size were used to determine the difference of the variables of interest between the original and fore-medial-side thin insoles. The fore-medial-side thin insole showed less foot inversion angle at contact, peak ankle lateral shear force and ankle dorsiflexion moment than the original insole in L-cut (p<.05). In V-cut, the fore-medial-side thin insole showed less hip internal rotation at contact than the original insole (p<.05). In the shuttle run, the fore-medial-side thin insole showed less hip abduction at contact than the original insole (p<.05). In case of foot pressure, it showed no statistically significant but had large effect size on left foot’s pressure time integral (PTI), in L-cut (≥0.8), large effect size on left foot’s PCP, PTI, right foot’s PTI in V-cut (≥0.8), large effect size on left foot’s peak contact pressure of 1st metatarsal (PCP), PTI, peak pressure gradient (PPG), right foot’s PTI in BD-cut (≥0.8), large effect size on left foot’s PTI, medium effect size on left foot’s PPG (≥0.5), and medium effect size on left foot’s the distance from the point of peak contact pressure to the medial edge of 1st metatarsal (PCPd) (≥0.5). In conclusion, the fore-medial-side thin insole can help to push our body to the medial side and decrease the risk of injuries of the lower extremity during cutting movements.

Effect of Modified High-heels on Metatarsal Stress in Female Workers

( Kwantae Kim ),( Hsien-te Peng ) 한국운동역학회 2019 한국운동역학회지 Vol.29 No.3

Objective: The purpose of this study was to identify the effect of high-heels (HH) modification on metatarsal stress in female workers. Method: Seven females who work in clothing stores (heights = 160.4±3.9 cm; weights = 47.4±4.1 kg; age = 31.3±11.1 yrs; HH wear career = 8±6.5 yrs) wore two types of HH (original and modified). The modified HH had been grooved with 1.5 cm radius and 0.2 cm depth around the first metatarsal area inside of the shoes using the modified shoe-last. Participants were asked to walk for 15 minutes on a treadmill and to stand for 10 minutes with original and modified HH, respectively. Kinetics data were collected by the F-scan in-shoe system. After each test, participants were asked to rate their perceived exertion using the Borg's 15-grade RPE scale and interviewed about their feeling of HH. Nonparametric Wilcoxon signed-rank test and effect size (Cohen's d) were used to determine the difference of the variables of interest between the original and modified HH. Results: In the present study, modified HH of the peak contact pressure of 1st metatarsal (PCP) left, PCP right, pressure time integral (PTI) left, peak pressure gradient (PPG) left during standing and PPG right during walking are greater than original HH. And even it didn't show statistically significant, the average in all pressure values of modified HH showed bigger than original HH. It surmised to be related to awkward with modified HH. Even though they said to feel the comfortable cause of big space inside of HH in the interview, they seemed to be not enough time to adapt with new HH. So their walking and standing postures were unstable. Conclusion: Modified the fore-medial part of HH can reduce the stress in the first metatarsal head and big toe area during standing and walking.

A 55.77 μW Bio-impedance Sensor with 276 μs Settling Time for Portable Blood Pressure Monitoring System

Kwantae Kim,Minseo Kim,Hyunwoo Cho,Kwonjoon Lee,Hoi-Jun Yoo 대한전자공학회 2017 Journal of semiconductor technology and science Vol.17 No.6

An ultra-low power bio-impedance sensor for wrist watch-type blood pressure monitoring system is implemented in 0.18 μm CMOS technology under 1.8 V supply. The duty-cycled current generator (DCG) enables low power and high amplitude current injection with 93.58% power reduction in a current generator block. A fast-settling readout circuit with DC balanced amplifier reduces settling time to 276 μs, allowing bio-impedance signal acquisition even when the motion artifact induced circuit transient occurs. The simulated 2.125 mm² single chip bio-impedance sensor consumes only 55.77 μW.

A 1.4-m <tex> $\Omega$</tex> -Sensitivity 94-dB Dynamic-Range Electrical Impedance Tomography SoC and 48-Channel Hub-SoC for 3-D Lung Ventilation Monitoring System

Kim, Minseo,Jang, Jaeeun,Kim, Hyunki,Lee, Jihee,Lee, Jaehyuck,Lee, Jiwon,Lee, Kyoung-Rog,Kim, Kwantae,Lee, Yongsu,Lee, Kyuho Jason,Yoo, Hoi-Jun IEEE 2017 IEEE journal of solid-state circuits Vol.52 No.11

<P>A wearable electrical impedance tomography (EIT) system is proposed for the portable real-time 3-D lung ventilation monitoring. It consists of two types of SoCs, active electrode (AE)-SoC and Hub-SoC, mounted on wearable belts. The 48-channel AE-SoCs are integrated on flexible printed circuit board belt, and Hub-SoC is integrated in the hub module which performs data gathering and wireless communication between an external imaging device. To get high accuracy under the variation of conductivity, the dual-mode current stimulator provides the optimal frequency for time difference-EIT and frequency difference-EIT with simultaneous 4 k-128 kHz impedance sensing. A wide dynamic range instruments amplifier is proposed to provide 94 dB of wide dynamic range impedance sensing. In addition, the 48-channel AE system with the dedicated communication and calibration is implemented to achieve 1.4-m Omega sensitivity of impedance difference in the in vivo environment. The AE-/Hub-SoCs occupy 3.2 and 1.3 mm2in 65-nm CMOS technology and consume 124 mu W and 1.1 mW with 1.2 V supply, respectively. As a result, EIT images are reconstructed with 90% of accuracy, and up to 10 frames/s real-time 3-D lung images are successfully displayed.</P>

An Ultra-low-power Mixed-mode Face Recognition Processor for Always-on User Authentication in Mobile Device

Ji-Hoon Kim,Changhyeon Kim,Kwantae Kim,Juhyoung Lee,Hoi-Jun Yoo,Joo-Young Kim 대한전자공학회 2020 Journal of semiconductor technology and science Vol.20 No.6

In this paper, we present an ultra-low-power analog-digital mixed-mode face recognition processor for user authentication in mobile devices. Unlike conventional face recognition processor architecture composed of an image sensor, high-resolution analog-to-digital converters (ADCs), and a digital signal processor, the proposed mixed-mode architecture removes the power-hungry ADCs and introduces an analog signal processor for processing the first layer of convolutional neural networks used by both face detection and face recognition as well as for performing ternary quantization. At the circuit level, we propose the reconfigurable readout circuit and exposure time-division scheme to integrate image sensor and analog signal processor without losing input data under various illumination conditions. We also propose the error-tolerant weighted-sum unit for analog convolution processing with only 15.09 uW power consumption. As a result, post-layout simulation results in 65 nm process demonstrate that the proposed mixed-mode face recognition processor has the total 0.205 mW power consumption while dissipating only 64 uW for always-on operation, which are 66.9% and 33.9% less than the state-of-the-art design.

Application of microwave-irradiation technique in deglycosylation of ginsenosides for improving apoptosis induction in human melanoma SK-MEL-2 cells

Choi, Pilju,Kim, Kwantae,Kim, Taejung,Park, Young-Tae,Song, Bong Geun,Shin, Myoung-Sook,Kim, Yong Ho,Hwang, Gwi Seo,Kang, Ki Sung,Ham, Jungyeob Pergamon Press 2019 Bioorganic & medicinal chemistry letters Vol.29 No.3

<P><B>Abstract</B></P> <P>To increase the contents of medicinally effective ginsenosides, we used high-temperature and high-pressure thermal processing of ginseng by exposing it to microwave irradiation. To determine the anti-melanoma effect, the malignant melanoma SK-MEL-2 cell line was treated with an extract of microwave-irradiated ginseng. Microwave irradiation caused changes in the ginsenoside contents: the amounts of ginsenosides Rg1, Re, Rb1, Rb2, Rc, and Rd were disappeared, while those of less polar ginsenosides, such as Rg3, Rg5, and Rk1, were increased. In particular, the contents of Rk1 and Rg5 markedly increased. Melanoma cells treated with the microwave-irradiated ginseng extract showed markedly increased cell death. The results indicate that the microwave-irradiated ginseng extract induced melanoma cell death via the apoptotic pathway and that the cytotoxic effect of the microwave-irradiated ginseng extract is attributable to the increased contents of specific ginsenosides.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Microwave irradiation facilitate deglycosylation of ginsenosides. </LI> <LI> Microwave irradiation caused changes in the ginsenoside contents. </LI> <LI> Less-polar ginsenosides induce apoptosis in melanoma. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

The Behavioral Analysis of Dance Sports Judge's Visual Searching Strategies: Focusing on the Skating System

( Mi-sun Kim ),( Ki-kwang Lee ),( Kwantae Kim ) 한국운동역학회 2020 한국운동역학회지 Vol.30 No.3

Objective: The purpose of this study was to investigate the differences between visual search, eye fixation positions, and eye fixation position on whole body regions while judging final matches of dance sports. Method: Ten experienced judges (male 6, female 4) and six dance sports couples belonging to the top Korean leagues in the Korea Dance sports Federation were participated. Wearable eye trackers were used for data collection. The independent t-test was conducted to examine the effects of gender, and the two-way ANOVA was conducted to examine the effects of judges' gender, dance event, and ranking. Results: It was found that the movement of male contestants was preferred, and the gaze fixation was high for torso movements in the judges' evaluations. Moreover, attention was focused on the upper body rather than the lower body; this was maintained for about seven seconds to evaluate each couple. Conclusion: This find was the relative comparison between the two couples was the determining factor in winning or losing.

최대교두감합위 및 하악 전방운동 시의 교합접촉 및 교합유도 양상에 관한 분석

김지연,김강현,노관태,김형섭,우이형,배아란,Kim, Jiyeon,Kim, Kang-Hyun,Noh, Kwantae,Kim, Hyeong-Seob,Woo, Yi-Hyung,Pae, Ahran 대한치과보철학회 2013 대한치과보철학회지 Vol.51 No.3

연구 목적: 저작 및 하악 운동시 발생되는 치아접촉은 치열의 보존, 하악의 안정과 보철 수복과정에 있어서 중요하다. 이에 한국인의 20-30대 성인을 대상으로 최대교두감합위에서의 치아접촉점의 위치 및 교합유도양상과 교합유도치의 분포를 분석하여 알아보고자 한다. 연구 대상 및 방법: 29명의 성인을 대상으로 하악의 최대교두감합위에서의 치아접촉점의 위치와 분포 및 전방운동시 교합접촉양상을 shimstock foil (Whaledent, Langenau, Germany), T-Scan III (Tekscan Inc., Boston, MA, USA), polyvinylsiloxane registration material (Genie Bite, Sultan Healthcare, Hackensack, NJ, USA)을 이용하여 측정하였다. 측정시 자세는 직립위로 Frankfurt horizontal plane과 지면이 수평이 되도록 앉게 하였으며 접촉이 재현될 때까지 수 차례 반복한 후 3회씩 측정하였다. 최대교두감합위에서 세가지 방법 간의 통계적 유의성을 비교하기 Fisher's Exact Test (R-General Public License, ver. 2.14.1)를 이용하였고, 전방 운동시 Pearson's Test를 통해 통계 검증하였다(${\alpha}=.05$). 결과: 최대교두감합위에서의 치아 접촉 양상을 shimstock foil, T-Scan III, polyvinylsiloxane registration material로 측정시 전치부, 소구치부, 구치부 모두에서 접촉하는 경우가 대부분이었으며, shimstock 사용시 약51%의 최대교두감합위는 전치부 접촉에서 일어났다. Shimstock foil과 T-Scan III를 사용하여 전방운동 측정시 중절치의 접촉이 가장 많이 일어났다. 결론: 최대교두감합위에서 실제 모든 치아의 접촉이 이루어지지 않는 경우가 있었으며 따라서 구치부에서 전치부를 보호해 주고 있음을 확인할 수 있었다. 또한, 전방운동 시 전치부의 치아접촉은 과도한 구치부의 치아접촉을 방지해 전치부가 구치부를 보호해 주고 있었다. 따라서 교합 재구성 시에는 이러한 상호 보호 교합에 대한 고려가 필요하다. Purpose: The importance of occlusal contacts of the natural dentition for durability of teeth, mandibular stabilization, and restorative dentistry is well known. The purpose of this study is to analyze the occlusal contact and guidance pattern of Koreans by evaluating the static occlusion on maximal intercuspal position and measuring dynamic occlusion during straight protrusion. Materials and methods: The occlusal contacts at maximal interincisal position and the occlusal guidance pattern during straight protrusion of 29 subjects were recorded with shimstock foil (Whaledent, Langenau, Germany), T-Scan III (Tekscan Inc., Boston, MA, USA), polyvinylsiloxane registration material (Genie Bite, Sultan Healthcare, Hackensack, NJ, USA) and compared. Occlusal registration procedures were repeated 3 times. The position was fixed to an upright position and the head position was fixed with the Frankfurt horizontal plane paralleling the horizontal plane. Fisher's Exact Test (R-General Public License, ver. 2.14.1) and Pearson's Test were used to assess the significance level of the differences between the experimental groups (${\alpha}=.05$). Results: When using shimstock foil, T-Scan III system, and polyvinylsiloxane registration material, most of the patients showed contact on anterior, premolar, and molar teeth during maximal intercuspal position. Approximately 51% of maximal intercuspal position showed anterior contact using shimstock foil. When examining the protrusive movement using shimstock foil and T-Scan III system, guidance pattern with the central incisor was the most common. Conclusion: During maximal intercuspal position, there were cases in which not all of the teeth showed occlusal contact. During mandibular protrusive movements, one or more maxillary central incisors frequently joined in straight protrusion and the posterior teeth were disoccluded. Therefore, the anterior teeth protect the posterior teeth, and vice versa. Thus, mutually protected occlusion should be applied when reconstructing occlusion.

의치사용자의 구강건강, 의치관리 및 의치건강보험 인식에 대한 실태 조사

김선재,김성균,노관태,안수진,백상현,김지환,유동기,김경록,권긍록,Kim, Sunjai,Kim, Seong-Kyun,Noh, Kwantae,Ahn, Su-Jin,Baik, Sang-Hyun,Kim, Jee-Hwan,Yoo, Dong-Ki,Kim, Kyoung-Rok,Kwon, Kung-Rock 대한치과보철학회 2018 대한치과보철학회지 Vol.56 No.4

Purpose: The aim of the present investigation was to understand the incidence, prevalence of denture stomatitis in denture wearers, who were over 60 years old, and use the results for a fundamental data to promote public awareness about denture stomatitis and its education tools. Materials and methods: From August 21 to September 8 2017, 500 denture wearers, who were more than 60 years old in Seoul and 4 other metropolitan cities (Busan, Daegu, Gwangju, and Daejeon), received questionnaires. The questionnaires included denture wearers' demographic distributions, specific dental treatment experiences, discomforts with current dentures, their oral health conditions, and the method of denture cleansing. Results: Thirty-two percent of 500 denture wearers responded that they have healthy oral conditions. Two hundred and eight respondents (41.6%) were aware of denture stomatitis. Only 131 (26.2%) were informed about the removable denture covered by national health insurance and 327 (65.4%) of denture wearers were using the improper denture cleansing methods. Conclusion: A large number of denture wearers still do not recognize the importance of proper treatment for denture stomatitis, insurance covered denture treatments, and adequate denture cleansing methods. 목적: 60세 이상의 의치사용자를 대상으로 구강 건강 상태, 의치 사용 및 관리 실태를 파악하여 올바른 의치 사용과 관리 중요성의 대국민 홍보 및 인식 제고를 위한 기초 자료로 활용하는 것이다. 대상 및 방법: 의치사용자의 구강건강상태, 의치성 구내염 현황 및 의치관리상태에 대해 2017년 8월 21일부터 9월 8일까지 서울 및 4대 광역시(부산, 대구, 광주, 대전)에서 60세 이상 남녀 중 현재 의치(총의치, 국소의치)를 사용하고 있는 자를 500명을 대상으로 조사하였다. 연구는 각 항목들에 대해 개별 면접 조사를 시행하였으며, 사용된 조사 항목은 응답자의 특성 8문항, 틀니 사용 현황 및 불편 경험 6문항, 구강 건강 상태(의치성 구내염 여부) 12문항, 틀니 관리 현황 7문항으로 구성되었다. 결과: 연구대상 의치사용자 중 161명(32.2%)은 본인의 구강 상태가 건강한 편으로 인식하고 있었고, 111명(22.2%)은 보통이라고 인식하고 있었다. 의치성 구내염은 208명(41.6%)에서 인지하고 있었다. 의치건강보험제도에 대해서는 조사대상자의 26.2%(131명)만이 인지하고 있었으며, 조사대상자의 65.4%(327명)의 의치사용자가 잘못된 의치 관리 방법을 사용하고 있었다. 결론: 본 연구에 따르면 의치사용자의 많은 수가 구강건강, 의치관리 및 의치건강보험에 대한 올바른 인식이 부족함을 알 수 있다.