• Journal of Biosystems Engineering
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• v.38 no.2
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• pp.138-148
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• 2013

Purpose: Determining an appropriate path is a top priority in order for a robot to maneuver in a dynamically efficient way especially in a pick-and-place task. In a non-standardized work environment, current robot arm executes its motion based on the kinematic displacements of joint variables, though resulting motion is not dynamically optimal. In this research we suggest analyzing and applying motion patterns of the human arm as an alternative to perform near optimum motion trajectory for arbitrary pick-and-place tasks. Methods: Since the motion of a human arm is very complicated and diverse, it was simplified into two links: one from the shoulder to the elbow, and the other from the elbow to the hand. Motion patterns were then divided into horizontal and vertical components and further analyzed using kinematic and dynamic methods. The kinematic analysis was performed based on the D-H parameters and the dynamic analysis was carried out to calculate various parameters such as velocity, acceleration, torque, and energy using the Newton-Euler equation of motion and Lagrange's equation. In an attempt to assess the efficacy of the analyzed human motion pattern it was compared to the virtual motion pattern created by the joint interpolation method. Results: To demonstrate the efficacy of the human arm motion mechanical and dynamical analyses were performed, followed by the comparison with the virtual robot motion path that was created by the joint interpolation method. Consequently, the human arm was observed to be in motion while the elbow was bent. In return this contributed to the increase of the manipulability and decrease of gravity and torque being exerted on the elbow. In addition, the energy required for the motion decreased. Such phenomenon was more apparent under vertical motion than horizontal motion patterns, and in shorter paths than in longer ones. Thus, one can minimize the abrasion of joints by lowering the stress applied to the bones, muscles, and joints. From the perspectives of energy and durability, the robot arm will be able to utilize its motor most effectively by adopting the motion pattern of human arm. Conclusions: By applying the motion pattern of human arm to the robot arm motion, increase in efficiency and durability is expected, which will eventually produce robots capable of moving in an energy-efficient manner.

• Food Science of Animal Resources
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• v.22 no.4
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• pp.337-342
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• 2002

This study was carried out to investigate the feeding effect of by-products such as ginseng loaves(GL) and stem (GS) which had about 8% of crude saponin on pork carcass and meat quality characteristics when they were fed for 40 days. The ginseng leaves and stem were added in feed and the pigs were slaughtered at 10, 20, 30 and 40 days. The chilled carcass weight and trimmed fat contents were higher(86.50 kg) in the pork fed for 40 days. The yields of fore legs were higher in pork fed for 10 days(P<0.05) and there was no different in the yields of the other portion cuts such as shoulder, rib, loin, belly, hind legs and tenderlons. The incidence of percentages for grade A and B decreased as the feeding periods increased up to 40 days. The backfat thickness was lowest in carcasses from pigs fed up to 20 days(P<0.05). The L values were highest in pork fed up to 30 days(50.22) and lowest(46.91) for pork fed 10 days. The incidence of PSE pork was low in pork fed for 20 days when compared to other feeding days. Cooking loss was lowest and water holding capacity(WHC) was highest in pork fed GL and GS stem, respectively. However, the analysis for accumulation contents of saponin and functionality in pork fed GL and GS is needed in the future research.

• The Journal of Korean Academy of Prosthodontics
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• v.40 no.2
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• pp.131-139
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• 2002

There have been many studies about marginal discrepancy of single restorations made by various systems and materials. But many of statistical inferences are not definite because of sample size, measurement number, measuring instruments. etc. The purpose of this study was to compare the marginal adaptations of the anterior single restorations made by different systems and to consider more desirable statistical methods in analysing the marginal fit. The in vitro marginal discrepancies of three different all-ceramic crown systems (Celay In-Ceram. Conventional In-Ceram. IPS Empress 2 layering technique) and one control group (PFM) were evaluated and compared. The crowns were made from one extracted maxillary central incisor prepared with a 1mm shoulder margin and $6^{\circ}$ taper walls by milling machine. 10 crowns per each system were fabricated. Measurements or a crown were recorded at 50 points that were randomly selected for marginal gap evaluation. Non-parametric statistical analysis was performed for the results. Within the limits of this study, the following conclusions were drawn: 1 Mean gap dimensions and standard deviations at the marginal opening for the maxillary incisor crowns were $98.2{\pm}40.6{\mu}m$ for PFM, $83.5{\pm}18.7{\mu}m$ for Celay In-Ceram, $104.9{\pm}44.1{\mu}m$ for conventional In-Ceram, and $45.5{\pm}11.5{\mu}m$ for IPS Empress 2 layering technique. The IPS Empress 2 system showed the smallest marginal gap (P<0.05). The marginal openings of the other three groups were not significantly different (P<0.05). 2 The marginal discrepancies found in this study were all within clinically acceptable standards ($100\sim150{\mu}m$). 3. When the variable is so controlled that the system may be the only one, mean value is interpreted to be the marginal discrepancy of a restoration which is made by each system and standard deviation is to be technique-sensitivity of each one. 4. From the standard deviations. the copy-milling technique (Celay/In-Ceram) was not considered to be technique-sensitive in comparison with other methods. 5. Parametric analysis is more reliable than non-parametric one in interpretation of the mean and standard deviation. The sample size of each group has to be more than 30 to use parametric statistics. The level of clinically acceptable marginal fit has not been established. Further studies are needed.

• Journal of the Korean Magnetics Society
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• v.6 no.6
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• pp.405-410
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• 1996

Valence band photoemission spectroscopy (PES) measurements have been performed for $Co_{x}Pd_{100-x}$ alloy films using synchrotron radiation (x = 0, 25, 40, 65). Then the partial spectral weight distributions (PSW's) of Co 3d and Pd 4d electrons have been determined. The Co 3d PSW's exhibit some structures which are quite different from those of the Co film for x < 25 %, whereas they become very similar to those of the Co film for x > 40 %. For x < 25 %, the peak near the Fermi level ($E_F$) and a shoulder around 2 eV binding energy in the Co 3d PSW reflect large hybridization between Pd 4d and Co 3d electrons, suggesting that the hybridization might play an inportant role in determining perpendicualr magnetic anisotropy. The Pd 4d PSW's in Co-Pd alloy films are found to have larger FWHM's (full widths at half maximum), larger binding energies of the main peaks, and larger spectral intensities at $E_F$ than the PES spectrum of the Pd film. The FWHM of the Pd 4d PSW increases with decreasing Pd concentration, which are considered to reflect the disordering effect in the alloy formation or the change in the Pd 4d electronic structure due to hybridization between Co 3d and Pd 4d electrons.

• Journal of Sasang Constitutional Medicine
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• v.20 no.2
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• pp.30-42
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• 2008

1. Objectives This paper was tried to find out the clinical use of Gwanjung-tang by comparing patients' chief complain and natural symptom. 2. Methods The study was researched as clinically with medical records of 88 patients who visited a certain oriental medicine clinic which is in Seoul during January, 2000 and June, 2006. 3. Results 1) The male patient who was treated with Gwanjung-tang(寬中湯) is rare. The rate of patients who visited clinic in her forties is 27.3%, in fifties is 18.2%, in thirties is 15.9%, in sixties is 12.5%, in twenties is 10.3%. 2) Chief complain which made patients to visit clinic is a chest pain(19.3%), back pain and shoulder pain (15.9%), edema (12.5%), headache (9.1%), irregular menstruation (8.0%), dyspepsia (8.0%), fatigue (8.0%), insomnia (5.6%), menopausal disorder (4.5%), lumbago (4.5%), abnormal condition of stools (2.3%), and abnormal condition of urine (2.3%). 3) Natural symptom is classified into appetite, digestion, stools, urine, sweat, and sleep. The rate of patients who complained abnormal condition of digestion is 71.6%, of sleep is 59%, of stools is 52.3%, of urine is 47.7%, if sweat is 34.1%, and of appetite is 30.7%. 4) The rate of patients who is treated with Gwanjung-tang between thirty and forty packs is 43.2%, twenty packs is 39.7%, between fifty and sixty packs is 5.7%, between seventy and eighty packs is 2.3%, and between ninety and hundred packs is 3.4%. 5) The rate of patients who is treated with Gwanjung-tang during 15 days is 45.5%, between 16 and 30 days is 26.2%, between 31 and 60 days 7.9%, between 61 and 90 days 3.4%, between 91 and 120 days is 4.5%, and more than 120 days is 12.5%. 6) There are not many cases that chief complain was abnormal condition of digestion (8.0%), sleep (5.6%) stools (2.3%), and urine (2.3%). But the rate of patients who complained discomfort of digestion(71.6%), sleep(59%) stools (52.3%), and urine (47.7%) is significantly high. 7) According to "Sasang Sin Pyeon", Gwanjung-tang was used in To-sa-gwak-ran (吐瀉藿亂), Hae-su (咳嗽), Jeok-chui (積聚), Pyo-han -bu-jong (表寒浮腫), Chang-man (脹滿), Chil-gi (七氣), Dam-um (痰飮), Dam-goe (痰塊), Seom-jwa-yo-tong (閃挫腰痛), Bi-tong (臂痛) of Soeumin, and it is corresponds with clinical cases for various components. 4. Conclusions Gwanjung-tang is a medicine of reconciliation, and it makes Stomach to be warm and take down Yin Qi. The most important effect of Gwanjung-tang is Sun-qi(順氣). So it is considerable that Gyejibanhasenggang-tang (少陰人 桂枝半夏生薑湯), Hyangsayangwi-tang (少陰人 香砂養胃湯), and Gwakhyangjunggi-san (少陰人 藿香正氣散) is also effective to symptoms above, because these are medicines of reconciliatio.

• Physical Therapy Rehabilitation Science
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• v.6 no.2
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• pp.83-89
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• 2017

Objective: Computers and smartphones have become a necessity for modern people, and the use of these things in an inappropriate position has increased the number of people who complain about neck problems. The purpose of this study was to compare the changes of cervical angle, range of motion (ROM) and pain threshold according to the McKenzie stretching and dry cupping therapy. Design: Cross-over design. Methods: We included 12 male and 6 female college students in their twenties, and conducted a pre- and post-test to evaluate the changes of each variable after the application of the McKenzie stretching and dry cupping therapy. Results: Neither the cervical spine angle nor the turtle neck angle showed any change in both the McKenzie stretching and the dry cupping treatment. In the McKenzie stretching, the pain threshold decreased, and the ROM of the cervical spine increased in all directions but there was no significant difference. The pain threshold was increased in the dry cupping treatment, and the ROM of the cervical spine was significantly increased in all directions (p<0.05). Comparisons of the McKenzie stretching and cupping treatment showed that the cupping treatment produced significantly greater pain thresholds and improvements in ROM of the cervical spine than the McKenzie stretching technique (p<0.05). Conclusions: Cupping treatment is more effective in improving ROM of the cervical spine and pain thresholds than the McKenzie stretching technique. In the future, cupping treatment will be one of the treatment options for pain and ROM impairments of the cervical spine.

• PNF and Movement
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• v.14 no.1
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• pp.7-14
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• 2016

Purpose: The purpose of this study was to determine the effectiveness of direct and indirect methods of contract-relax techniques in proprioceptive neuromuscular facilitation (PNF) stretching for improving hamstring flexibility. Methods: Twenty-six subjects were randomly assigned to either a direct contract-relax technique group or an indirect contract-relax group. For each group, stretching intervention was performed three times a week for a period of two weeks, with 12 seconds for the contraction and 10 seconds for the relaxation per once. The direct contract-relax technique for hamstring flexibility was applied by asking the subject to press down on the shoulder of the trainer in the straight leg-raising position. Conversely, the indirect contract-relax technique was performed by raising the leg with resistance. To facilitate a comparative analysis of hamstring flexibility between the two groups before and after the stretching intervention, two-way repeated ANOVA was performed. Hamstring flexibility for each group was measured using a passive straight leg-raising test. Results: The results showed significant improvement in hamstring flexibility for all subjects in the two groups. However, there was no significant difference between the groups. Conclusion: In conclusion, both direct and indirect contract-relax techniques are confirmed to be useful for improving hamstring flexibility. The choice of suitable technique has to be made individually according to the condition of each subject.

• Korean Journal of Applied Biomechanics
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• v.16 no.2
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• pp.97-108
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• 2006

C. H. OH, S. N. CHOI, T. G. NAM, The Kinematic Analysis of the Tennis Flat Serve Motion, Korean Jiurnal of Sports Biomechanics, Vol. 16, No. 2, pp. 97-108, 2006. By the comparison and the analysis of the different factors during the tennis flat serve motion such as the required time per section, the movement displacement of the racket, the velocity of the upper limbs joints, the physical center of gravity, and the angle and the angular velocity of the upper limbs joints between an ace player and a mediocre player, these following results were drawn. First, the experiment result of the total time required per section in a tennis flat serve motion showed that an ace player was faster than a mediocre player by 0.4 seconds. This result suggested that it was required to increase the speed of the racket head by a swift swing to perform an effective flat serve motion. Second, the experiment result of the movement displacement of the racket in the tennis flat serve motion showed that an ace player greatly moved toward the left side on an x-axis. But both an ace and a mediocre player were shown to be at the similar points on a y-axis at the moment of the impact of the racket. An ace player was also shown to be located at a higher position on a z-axis by 0.23m. Third, the velocity of the center of gravity of an ace player was faster in every phase than that of a mediocre player in a tennis flat serve motion. Fourth, the velocity of the upper limb joints of an ace player was faster in every phase than that of a mediocre player in a tennis flat serve motion. Fifth, the experiment result of the speed of the racket head in tennis flat serve motion showed that a mediocre player was faster than an ace player in the first phase, but the latter was faster than the former in the second, third, and the fourth phases. Sixth, at the moment of impact of a tennis flat serve, an ace player had greater flexion of the angle of the wrist joints by an 11.8 degree than a mediocre player. An ace player also had greater extension of the angle of the elbow joint and the shoulder joint respectively by a 5.2 degree and a 1.4 degree with a mediocre player. Seventh, an ace player had greater angular velocity of the upper limb joints and the hip joints than a mediocre player at the moment of the impact of tennis flat serve. Eighth, an ace player was shown to have a greater change of the forward and the backward inclination (or the anterior and posterior inclination) of the upper body

• Korean Journal of Applied Biomechanics
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• v.17 no.1
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• pp.165-174
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• 2007

The subject of this study was male apparatus gymnastics athlete who had scored high points doing basket with 1/2 turn on parallel bars. Then 3D motion analysis were used to calculate & analyse kinematic variables of Basket with 1/2 turn to Handstand. 1. The total average time spent for Basket with 1/2 turn took $2.16{\pm}.08sec$, at the downward upward phase took $.58{\pm}0.00sec$, $.23{\pm}.00sec$, at flight phase took $.28{\pm}.01sec$, at connected area phase took $.72{\pm}0.21sec$, at rotation area phase took $.35{\pm}.14sec$. To have a successful performance, there should be faster speed and velocity to rotate at the downward upward phase, then the upward velocity and height must be used adequately. Moreover, the speed must be faster at the flight connect phase to stabilize Center of Mass(CM) for the body, and must secure more time at the rotation area to have more stable performance. 2. After handstand on parallel bars while moving CM to right hand side, and It must be performed with big and magnificent performance with putting both hand's center to far away from the parallel bars. 3. Furthermore, CM must be moved fast from downwards to right hand side, and CM must be moved fast in vertical movement at upward and flight phase to avoid CM from moving back and forth, and left and right. 4. At downwards, the subject must rotate as bis as possible using hip-joint as wide as possible and at upwards, must put his body to vertical to have stable performance. While rotating or turning, it is better to do with bigger shoulder angle and have to make sure that trunk angle must be not scattered. To perform better and more positive in basket with 1/2 turn on parallel bars, the centrifugal force must be used big and fast at downward, and at upward and flight phase, downward movement must change to vertical movement as soon as possible while turning movement must happen at handstand position. Time spent must be shorten at connected area to stabilize CM and turning must be natural as possible while securing the necessary time of movement to well-balanced. Also, the body must be vertically closed from the ground.

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.4
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• pp.395-401
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• 2012

Purpose: The purpose of this study was to research any effect on vision protecting or decreasing VDT syndrome of extracted anthocyanine from fermented purple sweet potato and blueberry. Methods: Subjects were aged 19-20 years old who do not have ophthalmic and systemic diseases and over -N4.00 D of refraction error. 40 mg of extracted anthocyanine from fermented purple sweet potato, from blueberry, and control group, placebo were dosed at separate try. After 2 hours later, subjects were directed perform visual display terminal (VDT) work for 2 hours. Objective refractive error was measured before dosing anthocyanine and after VDT work for 2 hours. Degree of head ache, eye pain and strain and subjective symptoms of neck, shoulder and waist was also examined through interviews by dividing its degree into severe, moderate, slight or none. Results: After 2 hours VDT work, vision protection effect in terms of refractive error for dominant eye was decreased by $0.031{\pm}0.21$ D in the group of extracted anthocyanine from fermented purple sweet potato, $0.006{\pm}0.32$ D in the group of extracted anthocyanine from blueberry. However, there was significantly myopic progression in the placebo group by $0.144{\pm}0.28$ D (t=2.27, p=0.03). Conclusions: It is considered that extracted anthocyanine from fermented purple sweet potato inhibits increase of refraction anomalies of dominant eye rather than non-dominant eye after VDT work.