• IEIE Transactions on Smart Processing and Computing
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• v.4 no.5
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• pp.371-378
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• 2015

In this paper, a different type of pulse width modulation (PWM) control scheme for a buck converter is introduced. The proposed buck converter uses PWM with frequency hopping and a low quiescent.current low dropout (LDO) voltage regulator with a power supply rejection ratio enhancer to reduce high spurs, harmonics and output voltage ripples. The low quiescent.current LDO voltage regulator is not described in this paper. A three-bit binary-to-thermometer decoder scheme and voltage ripple controller (VRC) is implemented to achieve low voltage ripple less than 3mV to increase the efficiency of the buck converter. An internal clock that is synchronized to the internal switching frequency is used to set the hopping rate. A center frequency of 2.5MHz was chosen because of the bluetooth low energy (BLE) application. This proposed DC-DC buck converter is available for low-current noise-sensitive loads such as BLE and radio frequency loads in portable communications devices. Thus, a high-efficiency and low-voltage ripple is required. This results in a less than 2% drop in the regulator's efficiency, and a less than 3mV voltage ripple, with -26 dBm peak spur reduction operating in the buck converter.

• Clinics in Shoulder and Elbow
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• v.2 no.1
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• pp.35-40
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• 1999

Impingement syndrome is caused by a conflictual status between rotator cuff, subacromial bursa and anatomic and functional coracoacromial arch. The purpose of this study was to assessment the coracoacromial arch by MRI and to determine major factors among five components of coracoacromial arch. We analyzed forty-two cases of clinical impingement sign and test positive and postoperative confirmed diagnosed from March, 1991 to January, 1999. We evaluated acromial end abnormality according to the Bigliani acromial type and formation of osteophyte. Clavicular end abnormality classified flat, outward protrusion, inward protrusion to coracoacromial arch. Acromioclavicular joint abnormalities were advanced osteoarthritis and positive signal change. Coracoacromial ligament thickening was above 2 mm in oblique sagittal image. Coracoid process abnormality was inward protrusion to coracoacromial arch. All consecutive patients abnormalities were as follows: clavicular end osteophyte formation and inward protrusion to coracoacrmial arch were 30%, acromial end osteophyte formation was 28%, advanced acromioclavicular joint arthritis and osteophyte formation were 56%, coracoacromial ligament thickening was 24% and no coracoid process inward protrusion to coracoacromial arch. Impingement syndrome combined with rotator cuff tear group abnormalities were clavicular end(40%), acromial end(40%), acromioclavicular joint(20%), coracoacromialligament(20%) and coracoid process abnormality(0%) respectively. Only impingement syndrome group abnormalities were clavicular end(25%), acromial end(31%), acromioclavicular joint(62%), coracoacromial ligament(25%) and coracoid process(0%) respectively. Acromial type I(flat) were 6 cases, type II(curved) were 26 cases and type III(hooked) were 10 cases. We concluded that the most important contributing factors for impingement syndrome was acromial type and second was acromioclavicular joint arthritis and bony spur formation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.11
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• pp.1327-1334
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• 2012

This study shows the conformance-based design results of a fourth-order dynamic actuator showing a performance variation caused by variation in the components as well as aero-induced disturbances. The actuator comprises a BLDC motor, spur gear and worm gear assembly, and canard. The actuator performance was evaluated by using time-variant angle information of the canard. Based on the response surface models, critical system variables were screened using F-tests, and then, the performance was approximated as a function of the variables because it is difficult to determine the performance of a high-order dynamic system as a function of system variables through analytical approaches. In this study, the conformance of uncertain performance to the specification was defined as a probability measure. The design variables obtained by optimizing the measure can provide actuator performance conforming to the specifications considered, even though there is a variation in both the components and the aero-induced disturbances.

• Journal of Chest Surgery
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• v.28 no.8
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• pp.766-771
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• 1995

The trachea is defined as the airway from the inferior border of the cricoid cartilage to the top of the carinal spur. This paper would confirm the normal tracheal length of Korean adults through the actual measurement using the fiberoptic bronchoscopy. The subjects of this study were 25 patients, 13 males and 12 females between the age of 20 to 69 without abnormality on the neck, trachea, mediastinum and lung pharenchyme on the preoperative chest X-ray, who received the operations from the period of July to September, 1994. For those patients who had heart diseases, the cardiothoracic ratio was below 50%. The measurement was performed on the patients with endotracheal intubation under the general anesthesia in supine and neutral position. The tracheal length was calculated by the difference between the length from the tip of the endotracheal tube [E-tube to carina and to the needle which was inserted into the E-tube at the lower border of the palpated cricoid cartilage, by inserting the broncoscopy through the E-tube. The result was as follow : 1 The measured tracheal length for men was 11.8 0.2 cm[mean standard deviation and women was 10.5 0.3 cm, and that was longer than this [p<0.01 . The average was 11.2 1.0 cm and the standard error was 0.20 cm. 2 According to the correlation between the tracheal length to weight, height[Ht , age, and body surface area[BSA respectively, the Ht [p=0.003 , age [p=0.055 , and the BSA[p=0.017 were significant, while weight was not [p=0.314 . 3 From the regression analysis of the tracheal length[T.L. to the Ht, Age, and the BSA which were significant, the following equation was derived.i Ht : T.L.= -1.29 + 0.076 x Ht [P=0.003 ii Age: T.L.= 10.04 + 0.028 x Age [P=0.055 iii BSA : T.L.= 5.60 + 3.48 x BSA [P=0.017 iv In multi-regression : T.L. = -4.15 + 0.034 x Age + 0.085 x Ht [P=0.0002]

• The Journal of the Korea Contents Association
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• v.17 no.12
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• pp.247-256
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• 2017

21st century has become an era can design human's image. By designing the each human's images it is possible to express the hidden abilities of their mind. Modern society changes rapidly where the elements such as consideration, sympathy, understandings, and female leadership of communication emerge as a spur rather than speediness or complexity.In a lot of global conglomerates, it is very common for women to be selected as CEO, and even more, the rate of woman who are the member of Congress is almost 40%. The fashion of female leader has come to the fore with an improvement of female leadership, and the fashion colour which is suitable to P.O has been developed as a significant image strategy. I am going to conduct the research and analyse the fashion of a female political leader through the colour image which is equivalent to a visual image and sensitive language. I will analyze the human image which female leaders present through fashion colors.

• Journal of Korean Neurosurgical Society
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• v.29 no.1
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• pp.87-94
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• 2000

Objective : Various surgical approaches have been implemented to fulfill the ideal goals of treatment for cervical spondylotic lesions. Conventional approaches are represented by anterior approach with or without fusion and posterior approach. The authors has applied newly developed anterior cervical microforaminotomy for these lesions on minimally invasive basis. Materials and Method : Twenty-one patients, with cervical HIVD, or stenosis, or both, underwent anterior cervical microforaminotomy between March, 1998 and April, 1999. Fifteen patients underwent unilateral decompression, and 6 bilateral decompression via unilateral foraminotomy. Operation of one level was performed in 16 patients, 2 levels in 4 patients, and 3 in 1 patient. The foraminotomy was accomplished by resecting the uncovertebral joint. Through this hole, compressed nerve root was decompressed by removing the spondylotic spur or disc fragment, and diagonal removing of posterior osteophyte from foraminotomy site to begining of contralateral nerve root made spinal cord decompression. Results : The outcome was excellent in 17 patients(81%) and good in 4 patients(19%) based on Odom's criteria. No complication was encounterd, and average post-operation hospital stay was 3.7 days. Conclusions : These results indicate that anterior cervical microforaminotomy provide adequate neural decompression, minimum postoperative discomfort and fast recovery.

• Journal of Arbitration Studies
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• v.19 no.1
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• pp.45-65
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• 2009

China and Taiwan had opened complete Three Linkages era December 2008, in the 59 years. The improvement of two countries' relationship is expecting to spur two countries more on the economy exchange. However the increasement of investment and trade between two countries will increase disputes to ratio. In order to settle the disputes related to economy between two countries, the most favorite way is to use arbitral system which involve less public power. After China and Taiwan recognized this point, they announced provisions which allow to solve controversies through the arbitration between parties of two countries since 1980, and prepared legal basis for dispute settlement between two countries. However, because China and Taiwan do not authorize each party as a country, the execution application made by each party based on New York Convention related to foreign arbitral awards cannot be approved. Because of these kind of reasons China and Taiwan should agree in order to guarantee mutual execution of arbitral awards which is an ultimate purpose of arbitration. However because of the political situation of two countries there are provisions related to execution for arbitral awards decided by each party. In this paper, I separated the provision related to mutual execution for arbitral awards of each party of China and Taiwan, examined exposed problems, and suggested ways to improve. It can support some of assistance and implication to establish basis of arbitral system between South Korea and North Korea and to suggest direction to derive through this kind of study.

• The Journal of the Korean bone and joint tumor society
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• v.13 no.1
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• pp.55-59
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• 2007

Synovial chondroma is an uncommon benign lesion characterized by metaplastic cartilage formation within the synovial connective tissue, usually intraarticular, commonly affects the knee, hip and elbow. We would like to present the case of a 65-year-old man suffering from synovial chondroma of the right elbow responsible for radial nerve entrapment neuropathy. This is a case of synovial chondroma of the right elbow in an 65-year-old man presenting with pain and restricted joint movement of the right elbow, loss of extension and sensation of the right thumb and wrist. Plain radiographs showed narrowing of elbow joint space, bony spur on the edge of the joint, and radio-opaque sclerotic change of subchondral area. MRI revealed $16{\times}12$ mm sized round mass on the radial head, homogenous low signal on T1WI, heterogenous high and low signal on T2WI. The patient underwent marginal excision of the mass, compressing the radial nerve. Diagnosis was confirmed by histologic examination.

• Animal Systematics, Evolution and Diversity
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• v.27 no.1
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• pp.25-33
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• 2011

Three morphospecies of the genus Uronychia, i.e. U. setigera Calkins, 1902, U. binucleata Young, 1922, and U. multicirrus Song, 1997, were collected from the coastal waters of Gumjin-ri on the East Sea and the public waterfront of Incheon on the Yellow Sea in Korea, respectively. These species are described based on live observation, protargol impregnation, silver nitrate impregnation, and their morphometrics. Diagnostic keys for these species are also provided. In addition, their small subunit ribosomal DNA sequences were compared with previously known sequences of Uronychia species. Diagnostics of three Uronychia species are as follows: U. setigera: $50-80\;{\mu}m$ long in vivo, oval-shaped, 2 macronuclear nodules (Ma), 1 spur on the left margin, 11 adoral membranelles (AM) 1, 4 AM2, 1 buccal cirrus (BC), 4 frontal cirri (FC), 3 left marginal cirri (LMC), 2 ventral cirri (VC), 5 transverse cirri (TC), 3 caudal cirri (CC), 6 dorsal kineties (DK), and approximately 23 cilia in the leftmost kinety. U. binucleata: $70-110\;{\mu}m$ long in vivo, oval to slightly rectangular shaped, 2 Ma, 1 micronucleus (Mi), 2 spurs on the posterior region, 11 AM1, 4 AM2, 1 BC, 4 FC, 3 LMC, 2 VC, 5 TC, 3 CC, 6 DK, and approximately 37 cilia in the leftmost kinety. U. multicirrus: $140-200\;{\mu}m$ long in vivo, oval to slightly rectangular shaped, ca. 7 Ma, 1 Mi, 11 AM1, 4 AM2, 1 BC, 4 FC, 3 LMC, approximately 8 VC, 5 TC, 3 CC, and 6 DK. This study presents the first record of this genus in Korea.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.6
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• pp.860-866
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• 2016

An injection-locked ring phase-locked loop (ILRPLL) using a charge-stored complementary switch (CSCS) injection technique is described in this paper. The ILRPLL exhibits a wider lock range compared to other conventional ILRPLLs, owing to the improvement of the injection effect by the proposed CSCS. A frequency calibration loop and a device mismatch calibration loop force the frequency error to be zero to minimize jitter and reference spur. The prototype chip fabricated in 65-nm CMOS technology achieves a $285-fs_{rms}$ integrated jitter at GHz from the reference clock of 52 MHz while consuming 7.16 mW. The figure-of-merit of the ILRPLL is -242.4 dB.