• Journal of the Society of Naval Architects of Korea
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• v.30 no.1
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• pp.30-44
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• 1993

This paper deals with both experimental and theoretical methods for performance prediction of asymmetric stater propulsion systems which have been used for the purpose of recovery of a propeller slipstream rotational energy due to a stator located in front of the propeller. Using the developed computer code based on the lifting surface theory, theortical investigation on the interaction between the stator and the propeller is provided in order to obtain general insight on the performance characteristics of the propulsion systems in uniform and non-uniform flow. Such theoretical calculations have end agreements with model Inset results. The asymmetric stator would give an efficiency gain of about 6% to the compound propulsor system compared with the single propeller system.

• Current Optics and Photonics
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• v.5 no.5
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• pp.514-523
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• 2021

Methods for absolute depth estimation have received lots of interest, and most algorithms are concerned about how to minimize the difference between an input defocused image and an estimated defocused image. These approaches may increase the complexity of the algorithms to calculate the defocused image from the estimation of the focused image. In this paper, we present a new method to recover depth of scene based on a sharpness-assessment algorithm. The proposed algorithm estimates the depth of scene by calculating the sharpness of deconvolved images with a specific point-spread function (PSF). While most depth estimation studies evaluate depth of the scene only behind a focal plane, the proposed method evaluates a broad depth range both nearer and farther than the focal plane. This is accomplished using an asymmetric aperture, so the PSF at a position nearer than the focal plane is different from that at a position farther than the focal plane. From the image taken with a focal plane of 160 cm, the depth of object over the broad range from 60 to 350 cm is estimated at 10 cm resolution. With an asymmetric aperture, we demonstrate the feasibility of the sharpness-assessment algorithm to recover absolute depth of scene from a single defocused image.

• The Journal of Korean Physical Therapy
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• v.28 no.2
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• pp.124-127
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• 2016

Purpose: The flexor hallucis longus stretch test can determine the shortness of the flexor hallucis longus muscle by measuring the angle of extension in the first metatarsophalangeal (MTP) joint at maximum ankle dorsiflexion. Less than 30 degrees of the first MTP joint at the maximal ankle dorsiflexion indicates shortness of the flexor hallucis longus muscle. The purpose of this study was to examine the intra- and inter-reliability of the flexor hallucis longus stretch test in subjects with asymmetric hallux valgus (HV) angles. Methods: Sixteen subjects with asymmetric HV angles participated in this study. In sitting position, dorsiflexion angles of the first MTP joint were measured with maximum ankle dorsiflexion on each side. ICC (3,1) and ICC (3,k) models were used, respectively, to assess the intra-reliability and inter-reliability of the flexor hallucis longus stretch test. The paired-t test was used to compare the dorsiflexion angle of the first MTP joint on the side with the smaller HV angle with that of the side with the larger HV angle. Results: The results of the study showed that both intra- and inter-reliability were more than 0.95 of the coefficient. Dorsiflexion angle of the first MTP joint was higher on the side with the smaller HV angle. Conclusion: Use of the flexor hallucis longus stretch test is acceptable in clinical settings because both intra- and inter-reliability were high in subjects with asymmetric HV angles. In addition, shortness of the flexor hallucis longus muscle is associated with HV angle. This study provides useful information for use in management of HV deformity.

• The korean journal of orthodontics
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• v.43 no.5
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• pp.209-217
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• 2013

Objective: This study investigated whether temporomandibular joint (TMJ) condyle-fossa relationships are bilaterally symmetric in class III malocclusion patients with and without asymmetry and compared to those with normal occlusion. The hypothesis was a difference in condyle-fossa relationships exists in asymmetric patients. Methods: Group 1 comprised 40 Korean normal occlusion subjects. Groups 2 and 3 comprised patients diagnosed with skeletal class III malocclusion, who were grouped according to the presence of mandibular asymmetry: Group 2 included symmetric mandibles, while group 3 included asymmetric mandibles. Pretreatment three-dimensional cone-beam computed tomography (3D CBCT) images were obtained. Right- and left-sided TMJ spaces in groups 1 and 2 or deviated and non-deviated sides in group 3 were evaluated, and the axial condylar angle was compared. Results: The TMJ spaces demonstrated no significant bilateral differences in any group. Only group 3 had slightly narrower superior spaces (p < 0.001). The axial condylar angles between group 1 and 2 were not significant. However, group 3 showed a statistically significant bilateral difference (p < 0.001); toward the deviated side, the axial condylar angle was steeper. Conclusions: Even in the asymmetric group, the TMJ spaces were similar between deviated and non-deviated sides, indicating a bilateral condyle-fossa relationship in patients with asymmetry that may be as symmetrical as that in patients with symmetry. However, the axial condylar angle had bilateral differences only in asymmetric groups. The mean TMJ space value and the bilateral difference may be used for evaluating condyle-fossa relationships with CBCT.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.1
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• pp.37-44
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• 2016

Recently researchers are conducting a lot of research related to EEDI in order to satisfy IMO resolution MEPC. Especially they are interested in design of energy saving device. This paper is to design the asymmetric pre-swirl stator for 160K LNG carrier in order to reduce energy. Two types of the asymmetric pre-swirl stator are taken into account; constant and variable pitch angle stators. “constant” and “variable” mean state that the pitch of stators change by radius. The dimensions of the stators are initially determined using potential-flow code. The propulsion performances of the stators are predicted using viscous-flow code. The model test is carried out in towing tank in PNU. Prediction of ship performance generally follow ITTC recommended. Ship wake prediction was done by two method, ITTC 1978 and ITTC 1999. Therefore propulsion performances were compared ITTC 1978 with ITTC 1999 methods. Comparison components are delivered power and thrust deduction coefficient of the model. Final pre-swirl stator is selected by comparing experiment and CFD.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.13 no.1
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• pp.5-17
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• 2002

Objectives : Videostrobokymography(VSK) has been recently developed and reported by Sung et at. We aimed to analyze vibratory patterns and objective parameters in various benign vocal fold lesions using VSK, and examine the efficacy of VSK in clinical application. Materials and Methods : Using VSK, we analyzed the vibration pattern of normal vocal fold and various benign lesions, such as nodules, polyps, cysts, Reinke's edema and unilateral vocal fold paralysis. We also calculated objective parameters, open quotient and asymmetric index, and compared them with mean values of parameters in normal controls. Results : In nodules, polyps, and cysts, the open quotient on the site of the lesion was similar to the mean value in normal controls, however, on the other part of the vocal folds it was much larger than normal mean value. In Reinke's edema, irregular and asymmetric vibration was observed. The posterior portion of the vocal folds showed larger open quotients than the anterior portion. In the unilateral vocal fold paralysis, irregular vocal folds vibration and incomplete closure of the vocal folds were documented. Much larger asymmetric indices were calculated in the unilateral vocal fold paralysis than in normal controls and other lesions. The asymmetric index could be a good quantitative parameter of vibration from a patient with vocal fold paralysis. Conclusion : This study demonstrated that VSK could generate clear quantitative documentations of fine vibrations of vocal folds in many different benign lesions. VSK has a potential as an effective tool for quantitative analysis of vibratory patterns of the vocal folds iii clinical settings.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.40 no.1
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• pp.11-16
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• 2014

Objectives: The aim of this study was to evaluate the pattern of lingual split line when performing a bilateral sagittal split osteotomy (BSSO) for asymmetric prognathism. This was accomplished with the use of cone-beam computed tomography (CBCT) and three-dimensional (3D) software program. Materials and Methods: The study group was comprised of 40 patients (20 males and 20 females) with asymmetric prognathism, who underwent BSSO (80 splits; n=80) from January 2012 through June 2013. We observed the pattern of lingual split line using CBCT data and image analysis program. The deviated side was compared to the contralateral side in each patient. To analyze the contributing factors to the split pattern, we observed the position of the lateral cortical bone cut end and measured the thickness of the ramus that surrounds the mandibular lingula. Results: The lingual split patterns were classified into five types. The true "Hunsuck" line was 60.00% (n=48), and the bad split was 7.50% (n=6). Ramal thickness surrounding the lingual was $5.55{\pm}1.07$ mm (deviated) and $5.66{\pm}1.34$ mm (contralateral) (P =0.409). The position of the lateral cortical bone cut end was classified into three types: A, lingual; B, inferior; C, buccal. Type A comprised 66.25% (n=53), Type B comprised 22.50% (n=18), and Type C comprised 11.25% (n=9). Conclusion: In asymmetric prognathism patients, there were no differences in the ramal thickness between the deviated side and the contralateral side. Furthermore, no differences were found in the lingual split pattern. The lingual split pattern correlated with the position of the lateral cortical bone cut end. In addition, the 3D-CT reformation was a useful tool for evaluating the surgical results of BSSO of the mandible.

• The Journal of Natural Sciences
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• v.7
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• pp.47-51
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• 1995

In order to develope new asymmetric catalyst, we synthesized the following new sulfonamide derivatives start from S-Indoline-2-Carboxylic Acid via the following 5 steps. Hydroxy methyl derivative(1) was thus treated with methane sulfonyl chloride in the presence of triethylamine as base to give mesylated derivative(2) in 85% of isolated yield. The mesylate compound (2) was treated with excess sodium azide to give Azido derivative (4) in 95% isolated yield. Azido compound (3) was then reduced to the corresponding amino derivative in near quntitative yield by the hydrogenation under hydrogen atmospere in the presence of catalytic amount of Pd-C. The amino derivative (4) was converted to its sulfonamide derivatives by the treatment of compound(4) with triisopropyl benzene sulfonyl chloride in the presence of triethyl amine as base. Finally t-BOC group of the compound(5) was removed by the treatement of excess Trifluoro-acetic acid in near quantitative yield to give the target sulfonamide derivative (7) .in this paper we prepared compound(6) in 49% overall yield via the 5 steps of synthesis starting from t-Boc- 2-hydroxy methyl indoline(1) which cab be easily prepared from commercial available S-indoline-2-carboxylic acid by known methods. we plan to apply this new catalyst for the asymmetric reduction , diels-alder reaction, aldolcondensation reaction in due courses.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.27 no.3
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• pp.459-466
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• 2017

One of the most widely-used open source project; OpenSSL is a cryptography library that is used to secure most web sites, servers and clients. One can secure the communication with the Secure Socket Layer (SSL) or its successor, Transport Layer Security (TLS) protocols by using the OpenSSL library. Since cryptography protocols will be updated and enhanced in order to keep the system protected, the library was written in such a way that simplifies the integration of new cryptographic methods, especially for the symmetric cryptography protocols. However, it gets a lot more complicated in adding an asymmetric cryptography protocol and no guide can be found for the integration of the asymmetric cryptography protocol. In this paper, we explained the architecture of the OpenSSL library and provide a simple tutorial to modify the OpenSSL library in order to accommodate custom protocols of both symmetric and asymmetric cryptography.

• The KIPS Transactions:PartB
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• v.12B no.4 s.100
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• pp.459-464
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• 2005

The online game system could be largely divided into two parts: servers and clients. Clients accesses to a game server and analyzes the packets transmitted from a server. A game server manages users information and database. U a game server allows a new client to access the server to execute a game, it should accept the access request of the new client maintaining the online connection of the existing users. In this paper, we compare Process method and Thread method within the multiple jobs process methods of a server. Then we propose an asymmetric distributed multi server architecture that is adequate to asymmetric distributed architecture that is widely applied to most game servers. The proposed asymmetric distributed multi server architecture includes login server, game server, communication server and database server to perform its own feature independently. Comparing its other architectures, it shows better performance economically and technically. Especially it improves the stability and expandability of a server.