• Korean Journal of Applied Biomechanics
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• v.13 no.3
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• pp.265-276
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• 2003

The objective of this research is to provide basic data for improving athletic performances, suggesting methods that can be utilized at games and coaching movements in the snatch, by analyzing the level of contribution of muscles to the movements of the snatch lift through three-dimensional imaging and EMG analysis between skilled and unskilled lifters. To this end, three high school students (the skilled group), three middle school student (the unskilled group) were selected; two digital video cameras and electromyography were used. The muscles measured by an EMG include gastrocnemius muscle, biceps femoris muscle, erector spinae, latissimus dorsi muscle, trapezius muscle, and brachioradialis. Based on the Ariel Performance Analysis System (APAS) program, the results of the analysis are summarized as follows. 1. In performing snatch pulls, the skilled lifters were found to simultaneously move the weight centers of the body and the barbell close to vertical, close to the shoulders in the pulling portion; in snatching and grabbing the barbell from a sited position, it was observed that the shorter the time for adjusting to change in the height of the barbell by using rotational inertia, the better it is to perform the movements. 2. The skilled lifters were observed to perform stable and efficient movements in grabbing the bar in a sited position, by moving the barbell and weight center of the body close to vertical and moving the shoulder joint under the bar fast. 3. The results of the EMG analysis of the entire movements from the snatching portion to the portion of grabbing the bar in a sited position show that when the skilled lifters lifted the barbell vertically during the pulling portion, their shoulder joints were extended to put more weight on biceps femoris muscle and brachioradialis; and in snatching and grabbing the bar from a sited position, it was found desirable to increase the myoelectrical activity of erector spinae in order to achieve a balance in the movements of the hip joint between font and rear, as the weight centers of the body and the barbell move higher. On the other hand, the unskilled lifters were found that in response to change in posture, they increase their muscular strength inefficiently in performing the movements throughout the entire lifting process.

• Journal of Korea Port Economic Association
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• v.17 no.2
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• pp.89-110
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• 2001

Recent trends in globalization and informatization underscore the importance of logistics. As a result, there is a need for skilled and specialized logisticians. Third Party Logistics (TPL) and Supply Chain Management (SCM) require logisticians with a broad base of knowledge in areas such as multimodal transport, international trade, information technology computers, finance, operations management, etc. This study conducted a survey to find out the opinions of demanders and suppliers. The results of the surrey show that there are more skilled logisticians in the field of management, computer works in manager level and system management. The survey also found that the certificate exam, which the Ministry of Construction and Transportation started in 1997 as the "Certified Logistics Manager" exam, should have more questions in areas such as foreign languages, computers, logistics information, management skills, etc. To produce better logisticians in Korea, the government will have to invest more into their education, especially near the major ports and metropolitan areas. In addition, it is important that universities and companies work together to provide students with internship and other field-experience teaming opportunities. Logistics education centers should be built at the national level. In addition, the existing certification should be divided into two separate certifications: one for ordinary logistics, and one for international logistics. To further improve the certification system, short-answer or essay questions should be added to the second exam, and an additional certification for the highest level logisticians, a so-called "professional logisticians certificate," needs to be introduced.ntroduced.

• Korean Journal of Applied Biomechanics
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• v.27 no.2
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• pp.99-108
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• 2017

Objective: The purpose of this study was to analyze the effects of skill level and width between feet on kinematic and kinetic variables during jump rope single under with both feet. Method: Fifteen subjects in the skilled group (age: $10.85{\pm}0.40yrs$, height: $142.13{\pm}5.41cm$, weight: $36.97{\pm}6.65kg$) and 15 subjects in the unskilled group (age: $10.85{\pm}0.40yrs$, height: $143.31{\pm}5.54cm$, weight: $40.81{\pm}10.39kg$) participated in this study. Results: Participants in the skilled group minimized the anteroposterior displacement of their center of mass by modifying the width between their feet and decreased the range of motion (ROM) of their trunk in the sagittal plane. The preferred width during the jump rope decreased by 5.61~6.11 cm (32~37%) in comparison to width during static standing. The induced width was increased by 16.44~16.67 cm (82~85%), regardless of skill level. The kinematic variables of the left and right legs of members of the unskilled group were significantly different from those of members in the skilled group regarding the ROM of the hip, knee, and ankle joint. Otherwise, the members of the skilled group were consistent in terms of the kinematic variables of the right and left legs. Conclusion: The preferred width between feet during the jump rope was found to be beneficial for maintaining dynamic stability. The unskilled group exhibited asymmetry in left and right motion within the ranges of motion of the ankle, knee, and hip joints, regardless of the width. Therefore, long-term accurate jump rope motions will contribute to an improvement in the left and right imbalances of the entire body.

• Asia-Pacific Journal of Business
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• v.10 no.4
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• pp.87-118
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• 2019

The purpose of this study is to examine the effects of person-job fit, which consists of educational fit and skill fit, on employees' intrinsic job satisfaction. To the end, the 10-year balanced panel data of the Korean Labor and Income Panel Study(KLIPS) by the Korea Labor Institute (KLI) for 2008-2017 are utilized. This study analyzes 12,730 observations by 1,273 employees by using fixed effect model, random effect model, and pooled OLS estimation method. The empirical results are as follows: First, it is founded that educational fit and skill fit seem affect job satisfaction positively. Second, the negative effects of over-education are clear and the negative effects of under-education are unclear, while the effects of over-skilled and under-skilled are insignificant statistically. Third, the results imply that the size of effect of over-education on intrinsic job satisfaction is larger than that of the effect of over-skilled. Forth, it is shown that the use of fixed effect model is more effective and trustworthy than that of random effect model and pooled OLS estimation method, implying that the effect size of coefficients which are estimated by pooled OLS method and random effect model are likely over-estimated. The empirical results above imply that firms and employees should focus on solving over-education issue before all in order to enhance employees' job satisfaction and it is needed to monitor regularly whether systemic job assignment process is done based on the employees' educational attainment and skill level and to provide more chances for job re-allocation and job rotation.

• Korean Journal of Applied Biomechanics
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• v.27 no.3
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• pp.171-179
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• 2017

Objective: The purpose of this study was to perform a kinematic and kinetic analysis of double-under jump rope technique according to skill level and sex. Method: Participants comprised a skilled group of 16 (9 males, 7 females), and an unskilled group of 16 with 6 months or less of experience (9 males, 7 females). Five consecutive double-under successes were regarded as 1 trial, and all participants were asked to complete 3 successful trials. The data for these 3 trials were averaged and analyzed after collecting the stable third jump in each trial. The variables used in the analysis included phase duration, total duration, flight time, vertical toe height, stance width, vertical center of mass displacement, and right lower limb ankle, knee, and hip joint angles in the sagittal plane during all events. Results: The skilled group had a shorter phase and total duration and a shorter flight time than the unskilled group. The vertical center of mass displacement and ankle dorsiflexion angle were significantly smaller in the skilled group. The male group had a shorter phase duration than the female group. The vertical toe height was greater, the stance width was smaller, and the ankle and hip flexion angles were smaller in the male group. Conclusion: Variables that can be used to distinguish between skill levels are phase and total duration, flight time, vertical center of mass displacement, and ankle dorsiflexion angle. Differences between sexes in double-under jump rope technique may be related to lower limb flexion angle control.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.389-394
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• 1993

Die making process is classified into design,manufacturing,polishing,assembly, and performance test. Die polishing is not a machining process by cutting edge of tool, but it is finishing by relative cutting movement under the surface contact between grinding particles and workpiece, and this process comprised 30~40% of total manufacturing hours. However, die polishing process is still performed by the skilled workers. Now a days, it is very difficult to secure skilled workers due to the hardworking environment and this situation will be getting worse in the future which has great difficulty of dies and molds industries.This process has the common problem on the elimination of tedious manual polishing among the tool making industries. Therefore this study is aimed at the development of an automatic polishing attachment which could be attached onthe spindle of CNC machine tool and controlled by the NC program data created by CAD/CAM system. As a result, this study will contribute the realization of automatic fine polishing process and improvement of quality level of dies and molds.

• Journal of the military operations research society of Korea
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• v.37 no.1
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• pp.147-159
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• 2011

Recently, the military service period has been shortened continuously. Meanwhile, more skilled airmen are needed as the complexity of weapon systems increase. This phenomenon could lead to a disastrous result such as deteriorating the level of the readiness and the fighting power. We suggest a method to improve recruit's maintenance capability rapidly by assigning airmen to jobs appropriate to their characteristics using Datamining methods (K-menas and CART). We focus on the assigning method for air force's air-munition maintenance airmen since they are requested more skilled than other airmen. Grouping airmen with k-means method and devising classification rule with CART algorithm, we found that airmen's proficiency arrival period could be shortened by 1.79 months when they are assigned in the suggested way.

• Speech Sciences
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• v.10 no.3
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• pp.7-27
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• 2003

Esophageal Speech uses the esophageal air during phonation. Fluent esophageal speakers frequently intake air in oral communication, but unskilled esophageal speakers are difficult with swallowing lots of air. The purpose of this study was to investigate the difference of acoustic characteristics of vowel and consonants production according to the speech proficiency level in esophageal speech. 13 normal male speakers and 13 male esophageal speakers (5 unskilled esophageal speakers, 8 skilled esophageal speakers) with age ranging from 50 to 70 years old. The stimuli were sustained /a/ vowel and 36 meaningless two syllable words. Used vowel is /a/ and consonants were 18 : /k, n, t, m, p, s, c, $C^{h},\;k^{h},\;t^{h},\;p^{h}$, h, I, k', t', p', s', c'/. Fundermental frequency (Fx), Jitter, shimmer, HNR, MPT were measured with by electroglottography using Lx speech studio (Laryngograph Ltd, London, UK). 36 meaningless words produced by esophageal speakers were presented to 3 speech-language pathologists who phonetically transcribed their responses. Fx, Jitter, HNR parameters is significant different between skilled esophageal speakers and unskilled esophageal speakers (P<.05). Considering manner of articulation, ANOVA showed that differences in two esophageal speech groups on speech proficiency were significant; Glide had the highest number of confusion with the other phoneme class, affricates are the most intelligible in the unskilled esophageal speech group, whereas in the skilled esophageal speech group fricatives resulted highest number of confusions, nasals are the most intelligible. In the place of articulation, glottal /h/ is the highest confusion consonant in both groups. Bilabials are the most intelligible in the skilled esophageal speech, velars are the most intelligible in the unskilled esophageal speech. In the structure of syllable, 'CV+V' is more confusion in the skilled esophageal group, unskilled esophageal speech group has similar confusion in both structures. In unskilled esophageal speech, significantly different Fx, Jitter, HNR acoustic parameters of vowel and the highest confusions of Liquid, Nasals consonants could be attributed to unstable, improper contact of neoglottis as vibratory source and insufficiency in the phonatory air supply, and higher motoric demand of remaining articulation due to morphological characteristics of vocal tract after laryngectomy.

• Korean Journal of Applied Biomechanics
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• v.19 no.3
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• pp.467-479
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• 2009

The purpose of this study was to present the quantitative data which riders can utilize teaching field by comparison analysis of kinematics according to skill level of rider during 2 strides rising trot with the JeJu's-Horse. Participated subjects was consisted of total 10 riders(unskilled: n=5, skilled: n=5). The method of experiment & analysis was based on 3D cinematography. Variables were consisted of temporal, linear & angular kinematics by each event & phase. The skilled assigned more ratio of elapsed time in air than support phase, had the less range of motion in up-down direction and more consistent velocity in lateral & forward direction and performed periodic up-down movement with alignment in vertical direction according to elapsing of phases. The skilled more flexed at elbow and extended backwardly according to elapsing of phases, while more flexed forwardly at hip & knee and plantarflexion at ankle. The skilled postured backward extension but the unskilled do forward flexion. That is, It was considered that the unskilled continued more unstable posture than the skilled during 2 strides in rising trot.

• Journal of Labour Economics
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• v.30 no.2
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• pp.119-148
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• 2007

Foreign outsourcing, otherwise known as off-shoring, has become a matter of intense public debate and great concern in both developed countries and developing countries. Yet, there is a lack of good data on foreign outsourcing since the early 1990's. This paper presents updated measures of foreign outsourcing for the recent period. Its main findings are that the share of foreign-sourced goods in total manufactured inputs almost doubled-from 12.4 percent to 22.7 percent between 1987 and 2003. I then look at the relationship between the measure of foreign outsourcing activity and wages in US manufacturing industries in recent years from 1998 to 2003. The results show that for all workers, the outsourcing level is statistically significantly and negatively associated with industry wage premiums. The estimate suggests that a magnitude of 0.9 - a 9% decrease in industry wage premiums tends to accompany a 10% increase in industry outsourcing level. Outsourcing has a bigger effect on the less-skilled workers-industry outsourcing level increases by 10% and industry wage premiums decrease by about 11% in the case of less-skilled workers.