• International Journal of Human Ecology
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• v.10 no.1
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• pp.35-45
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• 2009

Six healthy female volunteers twice undertook an experiment with different types of clothing leaving the arms and legs covered or uncovered at $24{\pm}0.5^{\circ}C$ and $50{\pm}5%$ RH to study how different thermal stimulation to the distal extremities during the afternoon could modulate circadian parameters of body temperature rhythm. One type of clothing consisted of long-sleeved shirts and full-length trousers (Type I, 989 g, 0.991 clo); the other type consisted of half-sleeved shirts and knee-length trousers (Type II, 750 g, 0.747 clo). Subjects wore Type I or Type II clothing during the afternoon (14:00 h - 19:00 h), and Type I clothing during the evening (19:00 h - 22:30 h) and the night sleep (22:30 h - 06:00 h). Rectal temperature and skin temperatures at the arm and leg were measured continuously. Results were as follows: 1) The circadian amplitude of rectal temperature tended to be greater, and the acrophase was significantly earlier when wearing Type II rather than Type I clothing. 2) The circadian nadirs of skin temperatures of the arm and leg were significantly lower and the amplitudes were significantly greater with Type II clothing. In addition, the acrophase and bathyphase of the circadian rhythm of arm skin temperature were significantly earlier with Type II than Type I clothing. 3) The amplitude of rectal temperature was related closely with that of arm and leg skin temperature. These results suggest that a slightly cool thermal stress during the afternoon to the arms and legs exerted by wearing half-sleeved shirts and knee-length trousers induces a greater amplitude and a phase advance of the overt circadian rhythm of body temperature.

• Fibers and Polymers
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• v.6 no.4
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• pp.322-331
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• 2005

Graduated compression stockings (GCS) have been widely used for the prophylaxis and treatment of venous diseases. Their gradient pressure function largely related to their fabric structure and material properties. By combing fabric physical testing and wear trials, this study investigated the GCSs fabric structure and material properties at different locations along the stocking hoses, and quantitatively analyzed the effects of fabrics on skin pressure longitudinal and transverse distributions. We concluded that, Structural characteristics and material properties of stocking fabrics were not uniform along the hoses, but a gradual variation from ankle to thigh regions, which significantly influenced the corresponding skin pressure gradient distributions; Tensile (WT, EM) and shearing properties (G) generated most significant differences among ankle, knee and thigh regions along the stocking hose, which significantly influenced the skin pressure lognitudinal gradient distribution. More material indices generating significant gradual changes occurred in the fabric wale direction along stocking hose, meaning that materials properties in wale direction would exert more important impact on the skin pressure gradient performances. And, the greater tensibility and smoother surface of fabric in wale direction would contribute to put stocking on and off, and facilitate wearers' leg extension-flexion movements. The indices of WT and EM of stocking fabrics in series A have strong linear correlations with skin pressure lognitudinal distribution, which largely related to their better performances in gradual changes of material properties. Skin pressure applied by fabric with same material properties produced pronounced differences among four different directions around certain cross-sections of human leg, especially at the ankle region; and, the skin pressure magnitudes at ankle region were more easily influenced by the materials properties, which were considered to be largely related to the anatomic structure of human leg.

• The Korean Journal of Community Living Science
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• v.28 no.3
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• pp.365-375
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• 2017

The purpose of this study was to investigate the maximal elongation rate and area expansion ratio of human skin in various postures. Five males and five females (male: $23{\pm}2yr$ in age, $177.9{\pm}4.8cm$ in height, $76.7{\pm}8.8kg$ in body weight, $24.2{\pm}2.5$ in BMI, $16.2{\pm}3.4%$ in body fat; female: $22{\pm}1yr$, $163.2{\pm}3.6cm$, $51.4{\pm}2.7kg$, $19.3{\pm}1.6$, $27.4{\pm}6.7%BF$) participated in this study. Measurements were conducted using a pen and tape on the elbow, knee, wrist, shoulder, and neck. Subjects held postures so that each joint of the body regions was bent at its maximal level. The results were as follows: 1) The maximal elongation rate of skin showed a significant difference among the regions: $16.6{\pm}3.4%$ for the wrist, $22.4{\pm}5.5%$ for the neck (back), $37.6{\pm}11.3%$ for the shoulder, $42.6{\pm}10.0%$ for the knee, and $43.9{\pm}4.0%$ for the elbow (p<0.05). 2) The maximal expansion rate of the body surface area had the greatest values on the elbow ($93.7{\pm}6.4%$) and knee ($74.8{\pm}10.8%$). 3) No significant difference was found between males and females. In summary, maximal values of skin elongation and expansion rates in vivo were greater than in vitro values known from previous reports. These results can be applied to develop electronic fibers or textiles for wearable tight fit work clothing as well as fitness wear.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.8
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• pp.1051-1057
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• 2013

In this study, an automatic surface-strain measurement system called "ASIAS-bio" has been developed. This system can be used even in cases in which it is very difficult to apply a regular grid pattern necessary for measuring surface-strain, such as curved or uneven surfaces; surfaces damaged by corrosion or contamination; or soft materials such as rubber, foam, and biological tissues. This system works independently of the measurement conditions including the material and its surface condition, grid pattern and size, grid marking method, and degree of deformation. A comparison between the strain distributions of the sheet metal parts measured by using this system and those obtained by a commercial system showed that this system was sufficiently reliable. In addition, the deformation of the swine joint capsule and human knee skin was measured by using this system to demonstrate its usefulness.

• Korean Journal of Human Ecology
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• v.13 no.1
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• pp.153-158
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• 2004

With considerable development of comfortable and functional clothing in recent years, we need to evaluate the effects of garment pressure in daily wear on each parts of human body because the garment pressure is important to design the clothing. This study was designed to examine the effects of body postures on garment pressure on each parts of human body in the actual clothing conditions. All the data were collected from 50 volunteered subjects. The Garment pressure was measured in lune and December with 8 points CPMS clothing pressure system from scapular, upper am, elbow, under arm, front waist line, side waist line, abdomen, crista ilica, upper hip, middle hip, front thigh, back thigh, front knee and back knee. The postures of subjects were controlled with 3 positions such as standing (posture 1), sitting on the chair (posture 2), and sitting on the floor (posture 3) during measurement of clothing pressure. Clothing weights were more in men than in woman. It showed that clothing weights had no effects on the garment pressure. In this study, however, just the garment pressures on scapular and top of the hip increased significantly by clothing weight (p<. 05). Clothing horizontally pressed on scapular and top of hip but not on other parts. When subjects stood up, the garment pressure was the highest on the side waist. Especially, clothing pressure on the front waist point was lower than that of the left side waist. On the upper parts of the human body, the garment pressure of left side waist was the highest, and followed by front waist, crista ilica, and abdomen in order. When subjects were sitting on the chair, the garment pressure on the lower parts of the human body was the highest on the top of hip. When the subjects were sitting on the chair or on the floor, the surface area on their skin of hip and waist parts increased by postures. In addition, it showed that men felt more comfortable than women on higher clothing pressure level.

• Steel and Composite Structures
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• v.35 no.6
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• pp.779-788
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• 2020

Multi-Walled Carbon nanotubes (MWCNT) coupled with Silicone Rubber (SR) can represent applicable strain sensors with accessible materials, which result in good stretchability and great sensitivity. Employing these materials and given the fact that the combination of these two has been addressed in few studies, this study is trying to represent a low-cost, durable and stretchable strain sensor that can perform excellently in a high number of repeated cycles. Great stability was observed during the cyclic test after 2000 cycles. Ultrahigh sensitivity (GF>1227) along with good extensibility (ε>120%) was observed while testing the sensor at different strain rates and the various number of cycles. Further investigation is dedicated to sensor performance in the detection of human body movements. Not only the sensor performance in detecting the small strains like the vibrations on the throat was tested, but also the larger strains as observed in extension/bending of the muscle joints like knee were monitored and recorded. Bearing in mind the applicability and low-cost features, this sensor may become promising in skin-mountable devices to detect the human body motions.

• Journal of Sensor Science and Technology
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• v.29 no.4
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• pp.237-242
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• 2020

This paper deals with relative position estimation using a Kalman filter (KF) based on inertial sensors that have been widely used in various biomechanics-related outdoor applications. In previous studies, the relative position is determined using relative orientation and predetermined segment-to-joint (S2J) vectors, which are assumed to be constant. However, because body segments are influenced by soft tissue artifacts (STAs), including the deformation and sliding of the skin over the underlying bone structures, they are not constant, resulting in significant errors during relative position estimation. In this study, relative position estimation was performed using a KF, where the S2J vectors were adopted as time-varying states. The joint constraint and the variations of the S2J vectors were used to develop a measurement model of the proposed KF. Accordingly, the covariance matrix corresponding to the variations of the S2J vectors continuously changed within the ranges of the STA-causing flexion angles. The experimental results of the knee flexion tests showed that the proposed KF decreased the estimation errors in the longitudinal and lateral directions by 8.86 and 17.89 mm, respectively, compared with a conventional approach based on the application of constant S2J vectors.

• Fashion & Textile Research Journal
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• v.7 no.6
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• pp.665-672
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• 2005

The purpose of this study was to assess the feasibility and the effects of near infrared lighted garments on thermo-physiological responses in human body. Seven healthy adult men were recruited for this study. All subjects were informed the contents and purpose of this study. The experiment was carried out in a climate chamber of $32^{\circ}C$, 60%RH with 'Rest', 'Exercise' and 'Recovery' period. The experimental garments consisted of briefs, undershirts(sleeveless), nightclothes, T-shirts, knee-trousers and socks. Subjects participated in two experiments, one was wearing near infrared lighted garments(NIR-O), the other was wearing regular garments(NIR-X). The order of experiment was randomized, and subjects wore experimental garments before 24 hours in order to benefit by near infrared light. Measurement items included rectal temperature ($T_{re}$), mean skin temperature ($\bar{T}_{sk}$), sweat rate, heart rate, oxygen uptake and subjective sensation. The results are as follows: As to the variation of rectal temperature and mean skin temperature, value of wearing NIR-X was higher than value of wearing NIR-O, indicating a significant level of difference (p<.001). Sweat rate under NIR-O and NIR-X condition were 575.35 g and 535.75 g, respectively. Heart rate value of NIR-X condition was higher than NIR-O. Oxygen uptake measured during experiment was the higher in NIR-X condition with significant difference (p<.001). In the subjective sensation, the value of NIR-O condition was higher than NIR-X condition without significantly difference.

• Journal of Biomedical Engineering Research
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• v.22 no.5
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• pp.459-468
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• 2001

The Average Coordinate Referenee System (ACRS) method is developed to reduce experimental errors in human locomotion analysis. Experimentally measured kinematic data is used to conduct analysis in human modeling, and the model accuracy is directly related to the accuracy of the data. However. the accuracy is questionable due to skin movement. deformation of skeletal structure while in motion and limitations of commercial motion analysis system . In this study. the ACRS method is applied to an optically-tracked segment marker system. although it can be applied to many of the others as well. In the ACRS method, each marker can be treated independently. as the origin of a local coordinate system for its body segment. Errors, inherent in the experimental process. result in different values for the recovered Euler angles at each origin. By employing knowledge of an initial, calibrated segment reference frame, the Euler angles at each marker location can be averaged. minimizing the effect of the skin extension and rotation. Using the developed ACRS methodology the error is reduced when compared to the general Euler angle method commonly applied in motion analysis. If there is no error exist in the experimental gait data. the separation and Penetration distance of the femoraltibial joint using absolute coordinate system is supposed to be zero during one gait cycle. The separation and Penetration distance was ranged up to 18 mm using general Euler angle method and 12 mm using the developed ACRS.

• Journal of Nutrition and Health
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• v.39 no.2
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• pp.121-132
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• 2006

Minerals are extremely important in human metabolism, growth, and tissue repair. The risks of disturbances in mineral nutrition and metabolism are high following menopause. The aim of the study was to investigate the mineal nutrition status in middle-aged women (Pre & Postmenopausal) and the relation to climacteric symptoms. In the present study, we conducted the anthropometric measurement, climacteric symptoms survey and the dietary intakes including macronutrients, vitamins and minerals to assess the nutrient intakes. Also plasma mineral levels (Ca, P, Mg, Na, K, Fe, Cu, Zn) was measured. The participants were 105 middle-aged women (pre=51, Postmenopausal=54). The anthropometric measurement showed that 74% of subjects was overweight and obesity. The energy intakes were 83% of Korean EER. The macromineral intake (Ca, P, Mg, Na, K), Ca, P and Mg were 65%, > 116% and > 107% of Korean RI. Na and K intakes were > 243% and 53% of Korean AI. For the trace mineral intake (Fe, Cu, Zn), Fe, Cu and Zn intakes were 82%, > 146%, and 94% of Korean RI. The serum mineral concentration measurement, in case of Ca, Fe and Zn, > 10% of subjects showed lower level than normal clinical range. The most frequently appeared climacteric symptoms were dry eye, forgetfulness, difficult concentration, shoulder pain, fatique, depression & lonesomeness, backache, snore, dry skin, ankle & knee pain. In relation to mineral nutrition with climacteric symptoms, significant correlations have been founded between Ca intake and difficult concentration, Mg intake and snore, Fe & Zn intake and forgetfulness & dry skin, serum Ca concentration and forgetfulness, serum Na concentration and dry eyes & snore, serum K concentration and shoulder pain. From these results, it has been indicated that some mineral nutrition status may effect the prevention and reduction of climacteric symptoms in pre and postmenopause women.