• Journal of Power Electronics
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• v.4 no.3
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• pp.138-151
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• 2004

In this paper, a constant frequency phase shifting PWM-controlled voltage source full bridge-type series load resonant high-frequency inverter using the $4^{th}$ generation IGBT power modules is presented for innovative consumer electromagnetic induction heating applications, such as a hot water producer, steamer and super heated steamer. The bridge arm side link passive capacitive snubbers in parallel with each power semiconductor device and AC load side linked active edge inductive snubber-assisted series load resonant tank soft switching inverter with a constant frequency phase shifted PWM control scheme is evaluated and discussed on the basis of the simulation and experimental results. It is proved from a practical point of view that the series load resonant and edge resonant hybrid high-frequency inverter topology, what is called, DE class type, including the variable-power variable-frequency regulation function can expand zero voltage soft switching commutation area even under low output power setting ranges, which is more suitable and acceptable for newly developed induction heated dual pack fluid heaters. Furthermore, even the lower output power regulation mode of this high-frequency load resonant tank inverter circuit is verified so that this inverter can achieve ZVS with the aid of the single auxiliary inductor snubber.

• Journal of Acupuncture Research
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• v.37 no.4
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• pp.247-253
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• 2020

Background: Parkinson's disease(PD) affects not only motor symptoms, but also nonmotor symptoms. This study is a clinical trial to determine whether Qigong and acupuncture affect nonmotor symptoms of PD. Methods: A 2-arm parallel and randomized trial was performed with 21 participants who had received either Qigong meditation only [control group (CG)] or acupuncture and Qigong meditation [experimental group (EG)]. The participants' levels of the discomfort in nonmotor symptoms from Parkinson's disease were evaluated by using the Unified Parkinson's Disease Rating Scales (UPDRS 1) and Test of Smell Identification (TSI) before and after 12 treatments at baseline and 1 month after 12 treatments. Results: The both CG and EG showed improvements in the UPDRS 1 score after treatment by 5.6 ± 5.15 (p= 0.003; 74%) and 4.8 ± 3.80 (p = 0.004; 79%), respectively. The both CG and the EG did improvements in the TSI after treatment by 10.3 ± 4.37 (p < 0.001; 84%) and 12.6 ± 1.77 (p = 0.022; 100%), respectively. However, statistical differences were not observed between the CG and the EG using the UPDRS 1 and the TSI scores. Conclusion: The combination of Qigong and acupuncture and Qigong alone was shown to improve the nonmotor symptoms and olfactory function of PD. In the future, large-scale clinical studies on alternative treatment for PD and studies on mechanisms affecting nonmotor symptoms of acupuncture and Qigong are needed.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.75-80
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• 2013

Background: Breast cancer is the most common cancer diagnosed in females in Sri Lanka and early detection can lead to reduction in morbidity and mortality. Aim: To evaluate selected aspects of breast cancer early detection services implemented through well woman clinics (WWCs) in the Gampaha District. Methods: The study consisted of two components. A retrospective descriptive arm assessed clinical breast examination (CBE) coverage of target age group women (TGW) of 35-59 years in all the WWCs in Gampaha district over 2003-2007. A cross sectional descriptive study additionally assessed quality of breast cancer early detection services. The Lot Quality Assurance Sampling (LQAS) technique was used to decide on the lot size and threshold values, which were computed as twenty and six clinics. Checklists were employed in assessing coverage, physical facilities and clinic activities. Client satisfaction on WWC services was assessed among 200 TGW attending 20 WWCs using an interviewer-administered questionnaire. Results: CBE coverage in the Gampaha district increased only from 1.1-2.2% over 2003-2007. With regard to physical facilities, the number of clinics that were rated substandard varied between 7-18 (35-90%). The items that were lacking included dust bins, notice boards, stationary, furniture and linen, and cleanliness of outside premises and toilets. With regard to clinic activities, punctuality of staff, late commencement of clinics, provision of health education, supervision, CBE and breast self-examination (BSE) were substandard in 7-20 clinics (35-100%). Client satisfaction for WWC services was 45.2% (IQR: 38.7-54.8%) and only 11% had a score of ${\geq}70%$, the cut off set for satisfaction. Conclusions: Breast cancer early detection service coverage in the Gampaha district remained low (2.2%) in 2007, 11 years after commencing WWCs. All 20 clinics were substandard for overall CBE and BSE.

• Physical Therapy Korea
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• v.15 no.2
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• pp.30-37
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• 2008

Anticipatory postural adjustments are pre-planned by the central nervous system (CNS) before the activation of agonist muscles in the limbs, and minimize postural sway. Most previous studies on this topic have focused on upper-limb movement, and little research has been conducted on lower-limb movement. The purpose of this study was to investigate the recruitment order of left and right trunk muscles during limb movement. Fifteen healthy subjects (10 male, 5 female) were enrolled. Electro-myographic signals were recorded on the muscles of: (1) deltoid, lumbar erector spinae, latissimus dorsi and internal oblique during shoulder flexion, (2) rectus femoris, rectus abdominis, external oblique and internal oblique during hip flexion. During right upper limb flexion, the onset of left erector spinae muscle and left internal oblique muscle activity preceded the onset of right deltoid by 8.09 ms and 19.83 ms, respectively. But these differences were not significant (p>.05). A similar sequence of activation occurred with lower limb flexion. The onset of left internal oblique muscle activity preceded the onset of right rectus femoris muscle by 28.29 ms (p<.05). The onset of right internal oblique muscle activity preceded the onset of left rectus femoris muscles by 23.24 ms (p<.05). The internal oblique muscle was the first activated during limb movement. Our study established the recruitment order of trunk muscles during limb movement, and explained the postural control strategy of the trunk muscles in healthy people. We expect that this study will be used to evaluate patients with an asymmetric recruitment order of muscle activation due to impaired CNS.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.2
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• pp.63-68
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• 2005

Total 12 units of high power klystron-modulator systems as microwave source are under operation for 2.5 GeV electron linear accelerator in Pohang Light Source (PLS) linac. The klystron-modulator system has an important role for the stable operation to improve an availability statistics of overall system performance of klystron-modulator system. RF power and beam power of klystron are precisely measured for the effective control of electron beam. A precise measurement and measurement equipment with good response characteristics are demanded for this. Input power of klystron is calculated from the applied voltage and the current on its cathode. Tiny measurement error severely effects RF output power value of klystron. Therefore, special care is needed to measure precise beam voltage. Capacitive voltage divider (CVD), which divides input voltage as capacitance ratio, is intended for the measurement of a beam voltage of 400 kV generated from the klystron-modulator system. Main parameter to determine standard capacitance in the high arm of CVD is dielectric constant of insulation oil. Therefore CVD should be designed to have a minimum capacitance variation due to voltage, frequency and temperature in the measurement range. This paper will be present and discuss the design concept and analysis of capacitive voltage divider for a pulsed high-voltage measurement, and the empirical relations between capacitance effects and oil temperature variation.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.5
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• pp.562-571
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• 2008

In this paper, we propose a novel structure of a spiral antenna with a CP characteristic for RFID reader in UHF band. Since the proposed antenna can be built by printing on a FR-4 substrate, it is appropriate for low-cost mass-production. The antenna is designed to operate in UHF band of $860{\sim}960$ MHz. The CP bandwidth is Increased enough to cover an overall UHF RFID band by using a spiral structure for the antenna arm. The matching bandwidth is broadened by using a quarter-wave transformer between the fred and the antenna body. The proposed antenna has advantages of its easy gain and pattern control with a small antenna size. The measured antenna performance shows the matching bandwidth of 13%, the CP bandwidth of 23%, and the gain of 6.5 dBi. This verifies that the proposed antenna is appropriate for RFID antennas in UHF band.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.22 no.2
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• pp.35-39
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• 2016

Background: The superficial lymphatic system is divided into areas called lymphatic territories which are separated by watersheds. When the lymphatic system fails to remove its load either due to surgery, radiotherapy or some congenital malformation of it then the fluid and the proteins and wastes contained within it accumulates in that territory. Anastomotic connections exist across the watersheds and while they can work unaided manual lymph drainage (MLD) can significantly help drainage across them into unaffected lymphatic territories. The purpose of the study is to examine the effectiveness of a manual technique in moving fluids and softening hardened tissues using a tape measure and Patient-Specific Functional Scale. Methods: We examined the movement of fluids from the affected limbs of lymphedema patients who underwent a standardized 30-min treatment using the Dr. Vodder method of MLD. We chose a typical cross section of patients with secondary leg or secondary arm lymphedema. The lymphedema patient was also measured after the conclusion of treatment and underwent a follow-up control measurement, within 8 weeks. Both evaluation tools indicated a movement of fluid to different and unblocked lymphatic territories as well as a softening of tissues in some of the affected limbs. Results: MLD is an effective means of fluid clearance when it accumulates as a consequence of a failure of the lymphatic system. It seems likely that MLD has a systemic effect on the lymphatic system and that it can improve flow from otherwise normal tissues. Conclusions: It is hypothesized that a series of treatments would result in even more significant improvements.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.17 no.2
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• pp.101-110
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• 2007

This study was performed to find out hazardous factors in the loaded works of muscular skeletal disorders(MSDs) for four company attached to dining workers from October 2005 to June 2006. The results are summarized as follows. 1. 42.5% of workers in study group were 40-50 years old, and females were higher than males, and the average of body weight was 70kg, 57kg in males and females, respectively. Working time per day was mostly 7-9hours, and the rate of worker who had never education and training was 46%. 2. The upper part and right part of body were higher than lower part and left part in symptoms of muscular skeletal disorders. Body parts which complained of symptoms were the order of right shoulder(55%), right arm(54%), right hand,(40%) waist(35%), leg(25%), and neck(24%). 3. The results of evaluation in the loaded works of muscular skeletal disorders to cooking, dish supply, preparing side dish, and washing the dishes and cleaning the floor of cooking room using RULA and OWAS checklists was action level 4(potential hazards, needs of change workplace), and the result of evaluation using back compressive force needed control measures as 779.27 lbs~1,274.04 lbs. In a view point of the result of this study, large dining rooms should be designed by ergonomic technology for the work surface height, width, and depth. The height of carrying car should be lower to 70cm, and repetitiveness and handling weight should be reduced by mechanical means, and education and training also should be performed for all of workers positively.

• Therapeutic Science for Rehabilitation
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• v.2 no.1
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• pp.24-35
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• 2013

The Purpose of this study was to determine the clinical effectiveness of mirror therapy for stroke. Moreover, this paper was designed to summarize clarified information of neurological plasticity by mirror therapy to finally define the neurological mechanism. Mirror therapy improves the stroke patients' hand and arm motor function. It also has a positive influence on recovering performance of activities of daily living and relieving pain. However, it is not evident that mirror therapy restores visual neglect. There are various ways of recovering stroke. Fundamentally, all the theories are on a bases of restoration of premotor area. Premotor area which is associated with motor control increases the activation of primary motor area and finally improves patients' motor function. If primary motor area is completely damaged, premotor area and supplementary motor substitute for primary motor area. In summary of literature survey, there are not enough evidence to verify the effectiveness and neurological mechanism of mirror therapy. In future, more researches should be conducted to verify the neurological recovery through mirror therapy. Then, mirror therapy will be acknowledged as a clinically effective treatment.

• Journal of Chest Surgery
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• v.30 no.8
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• pp.809-814
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• 1997

Continuous epidural pain block with a local anesthetic agents is a commonly employed technique for pain relief after thoracotomy. In this study, we evaluated the effectiveness of the continuous epidural pain block in 19 patients undergoing elective lateral or posterolatrral thoracotomy with control group(n=19) from November 1994 to July 1995, Epidural lidocaine and morphine mixtures were injected via an epidural catheter as a bolus after operation, and then bupivacaine and morphine mixtures were injected continuously following 5 or 6 days. The pain score, upper arm elevation(ROM score), and respiratory rate were significantly changed(P<0.05) from 30min after injection. The CO2 tension of arterial blood was decreased significantly(P<0.05) from 2hr after injection. The postoperative hospital days were decreased significantly(P<0.05). Side effects of the epidural pain block were urinary retention(n= 10), urticaria(n=2) and a case of headache. There was no postoperative lung atelectasis. We conclude that the continuous epidural pain block is good for prevention of the postoperative lung complication and early recovery after thoracotomy.