• 한국전문물리치료학회지
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• 제26권2호
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• pp.1-7
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• 2019

Background: In previous studies, changes in postural alignment were found when the slope was changed during walking. Downhill walking straightens the trunk by shifting the line of gravity backward. Objects: This study investigated the effect of the downhill treadmill walking exercise (DTWE) on thoracic angle and thoracic erector spinae (TES) activation in subjects with thoracic kyphosis. Methods: A total of 20 subjects with thoracic kyphosis were recruited for this study. All the subjects performed the DTWE for 30 minutes. A surface EMG and 3D motion capture system were used to measure TES activation and thoracic angle before and after the DTWE. Paired t-tests were used to confirm the effect of the DTWE (p<.05). Results: Both the thoracic angle and TES activation had significantly increased after the DTWE compared to the baseline (p<.05). An increase in the thoracic angle indicates a decrease in kyphosis. Conclusion: The DTWE is effective for thoracic kyphosis patients as it decreases their kyphotic posture and increases the TES activation. Future longitudinal studies are required to investigate the long-term effects of the DTWE.

• PNF and Movement
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• 제17권1호
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• pp.93-101
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• 2019

Purpose: This study aimed to investigate lower extremity muscle activation to the variable weight shift on the affected side of patients with hemiplegia. Methods: Eighteen patients with chronic hemiplegia volunteered to participate in this study. All participants performed three types of weight shift (sideways, forward, and backward) in limits of stability on the affected side. Muscle activation in a paralyzed leg was measured with electromyography on the gluteus medius, tensor fasciae latae, rectus femoris, and biceps femoris; furthermore, the attached area was recommended by SENIAM projects. Each weight shift was performed three times, and then the mean value of the three measurements was analyzed. The data were analyzed by measuring the symmetrically standing position with the reference voluntary contraction (RVC) and was standardized with the percentage of RVC method. Results: No significant difference in lower extremity muscle activation occurred according to the three types of variable weight shift. However, significant differences in lower extremity muscle activation did occur with each weight shift position. In addition, activation increased at the rectus femoris and decreased at the gluteus medius and tensor fasciae latae. Conclusion: Hip abductor muscle strength training and variable weight shifts on the affected side must increase to improve patients'balance and limits of stability.

• 대한스포츠의학회지
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• 제36권4호
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• pp.197-206
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• 2018

Purpose: This study analyzed the muscle activity changes induced by motions of reaching forward and chest expansion that were examined from the bilateral muscles with rectus abdominis, external oblique, multifidus, and longissimus thoracic using Pilates cadillac instrument. Methods: Nine young adult women, who have no musculoskeletal disorder and any of chronic diseases, were participated. Surface electromyography system was used for recording of all signals produced by muscles, and then normalized as percentage of maximum voluntary isometric contraction (%MVIC). The paired t-test and repeated measures of analysis of variance was performed. Results: Reaching-forward motion showed a higher muscle activity from non-dominant external oblique muscle than that of the chest-expansion motion. During both reaching-forward motion and chest-expansion motion, MVIC values collected from dominant side of external oblique muscle were shown a significantly lower than the values obtained from non-dominant side (p<0.05). Conversely, %MVIC values in external oblique muscle collected from dominant side showed a significantly higher than the values obtained from non-dominant side of the same oblique muscle (p<0.05). Reaching-forward motion was caused a higher %MVIC on non-dominant external oblique muscle than that of the chest-expansion motion (p<0.05). Regardless of dominant or non-dominant sides, external oblique muscle was shown the highest activation rate of all the other muscles during reaching forward action, and longissimus thoracic muscle was shown the highest activation rate of all the other muscles during chest expansion action. Conclusion: Reaching-forward motion is suitable for activating an external oblique muscle, and chest-expansion motion is an effective enough in activating of longissimus thoracic muscle.

• 농업과학연구
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• 제48권3호
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• pp.597-606
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• 2021

Due to the characteristics of the farmland in Korea, forward and reverse shift is the most used. The fatigue of farmers is caused by forward and reverse shifting with a manual transmission. Therefore, it is necessary to improve the convenience of forward and backward shifting. This study was a basic study on the development of a current control system for forward and reverse shifting of agricultural tractors using proportional control valves and a controller. A test bench was fabricated to evaluate the current control accuracy of the control system, and the stability of the controller was evaluated through CPU (central processing unit) load measurements. A controller was selected to evaluate the stability of the proportional valve controller. The stability evaluation was performed by comparing and analyzing the command current of the controller and the actual current measured. The command current was measured using a CAN (controller area network) communication device and DAQ (data acquisition). The actual current was measured with a current probe and an oscilloscope. The control system and stability evaluation was performed by measuring the CPU load on the controller during control operations. The average load factor was 12.27%, and when 5 tasks were applied, it was shown to be 70.65%. This figure was lower than the CPU limit of 74.34%, when 5 tasks were applied and was judged to be a stable system.

• 복식문화연구
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• 제29권4호
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• pp.471-487
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• 2021

The purpose of this study was to analyze changes to body measurements and silhouettes after wearing an early 19th century women's corset. Two types of corsets were tested. Changes in body size and silhouette were compared based on the levels of tightening strength of the corset. The tightening strength was adjusted in 4 steps by making the length of back fastening string 10-40 cm shorter than the standard. The silhouette was compared with the front silhouette and the side silhouette. The results were as follows. After wearing the experimental 19th century corsets, the chest circumference and front interscye length increased. However, the chest circumference did not increase proportionally to the tightening strength. The underbust circumference, waist circumference, and back interscye length also decreased. The waist width was decreased to create a slim front silhouette. The change in the body silhouette differed depending on the style of the experimental corset. The experimental corset made with the six-piece torso pattern changed the posture so that the shoulders were pulled back and the chest was pushed forward. The experimental corset with the side bodice pattern resulted in the subject's shoulders reclining backward and the chest and abdomen extending forward. The results of this study show that women's body sizes and silhouettes could be changed by wearing the early 19th century corsets, but the changes in body size and silhouette vary depending on the wearer's individual body type or corset style.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2017년도 추계학술논문요약집
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• pp.74-74
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• 2017

Electrorefining is a key step in pyroprocessing. The electrorefining process is generally composed of two recovery steps - the deposit of uranium onto a solid cathode and the recovery of the remaining uranium and TRU elements simultaneously by a liquid cadmium cathode. Uranium deposit recovered from the solid cathode is a dendritic powder. It is necessary to separate the adhered salt from the deposits prior to the consolidation of uranium deposit. The adhered salt is composed of lithium, potassium, uranium, and rare earth chlorides. Distillation process was employed for the cathode processing. One of the operation methods is distillation of the salt at low temperature ($900^{\circ}C$), and then melting of the deposit at high temperature to avoid a backward reaction. For the development of the salt distiller, the distillation behavior of the low vapor pressure chlorides should be studied. Rare earth chlorides in the adhered salt of uranium deposits have relatively low vapor pressures compared to the process salt (LiCl-KCl). In this study, the evaporation rates of the lanthanum and neodymium chlorides were measured for the salt separation from electrorefiner uranium deposits in the temperature range of $825{\sim}910^{\circ}C$. The evaporation rate of both chlorides increased with an increasing templerature. The evaporation rate of lanthanum chloride varied from 0.12 to $1.68g/cm^2/h$. Neodymium chloride was more volatile than lanthanum chloride. The evaporation rate of neodymium chloride varied from 0.20 to $4.55g/cm^2/h$. The evaporation rate of both chlorides are more than $1g/cm^2/h$ at $900^{\circ}C$. Even though the evaporation rates of both chlorides were less than that of the process salt, the contents of the lanthanide chlorides were small in the adhered salt. Therefore it can be concluded that $900^{\circ}C$ is suitable for the operation temperature of the salt distiller.

• 공학교육연구
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• 제24권1호
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• pp.3-14
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• 2021

The purpose of this study is to analyze the characteristics of efficient problem-solving teams and inefficient problem-solving teams using SYMLOG. In this study, 35 college students majoring in engineering education at C university were organized into 7 teams and carried out technological problem solving projects over one semester. Based on the results of the team project, the top 2 teams were defined as efficient problem solving teams and the bottom 2 teams were defined as inefficient problem solving team, and analyzed the characteristics of the team using SYMLOG. The main results are as follows: First, an analysis of SYMLOG from efficient problem solving teams and inefficient problem solving teams showed that there was a difference between self-awareness and others' perception in terms of U(Upward)-D(Downward) dimension. Second, in the inefficient problem solving teams, there was a significant difference between self-awareness and others' in the F(Forward)-B(Backward) dimension. Third, there was no difference between self-awareness and others' in both efficient and inefficient teams at the P (Positive)-N(Negative) dimension. Fourth, an efficient problem-solving team had a clear leader, and there was a team member who supported the leader. On the other hand, the inefficient problem-solving team did not have a clear leader, or one person played the role of leader and there were no team members supporting the leader.

• 한국정보전자통신기술학회논문지
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• 제14권1호
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• pp.70-77
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• 2021

본 논문에서는 산업연관표와 한국표준산업분류를 비교하여 4차 산업혁명 관련 산업을 제조업, 정보통신서비스, 금융 및 보험서비스 그리고 과학기술서비스 4부문으로 재분류하였다. 그리고 수요유도형 모형을 이용해 4부문 산업을 외생화하여 경제적 파급효과를 분석하였다. 생산유발효과, 부가가치유발효과, 취업유발효과에 대한 분석결과, 제조업, 정보통신서비스 그리고 과학기술서비스 부문에서는 도소매 및 상품중개서비스가 큰 것으로 계측되었고, 금융 및 보험서비스 부문에서는 금융 및 보험서비스가 큰 것으로 분석되었다. 수입유발효과는 4차 산업 모든 부문에서 광산품이 가장 큰 것으로 분석되었다. 전후방연쇄효과 분석결과, 제조업과 정보통신서비스 부문은 경기변동에 민감한 중간수요적 원시사업형이고, 금융 및 보험서비스와 과학기술서비스 부문은 최종수요적 원시사업형임을 확인하였다.

• 한국산림과학회지
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• 제109권4호
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• pp.521-531
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• 2020

이 연구의 목적은 임업과 목재산업이 전체 경제에 미치는 영향 그리고 산업의 연관관계를 분석하는 데 있다. 이를 위해 한국은행의 2015년 산업연관표를 이용하여 임업과 목재산업 중심으로 재분류하고 경제적 파급효과와 다른 산업에 미치는 영향을 분석하였다. 생산유발효과는 종이제품 생산업, 제재업, 영림업에서 상대적으로 높게 나타났고, 다른 목재산업의 생산유발효과는 크지 않았다. 부가가치유발효과는 영림과 원목생산에서 높게 나타났다. 그리고 목재산업에서 후방연쇄효과보다 전방연쇄효과가 높게 나타나 경제 전체를 유지하는 데 중요한 것으로 나타났다. 다른 산업에 미치는 파급효과를 분석한 결과를 보면 목재산업의 생산증가가 임업에 미치는 파급효과가 크지 않은 것으로 나타났다. 목재산업과 임업은 산림생태계관리와 기후변화 대응에서 중요한 역할을 하므로 이들의 연관성을 높이는 것은 산림정책에서 중요한 정책과제이다.

• 대한치과교정학회지
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• 제51권2호
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• pp.105-114
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• 2021

Objective: The purpose of this study was to evaluate the relationship between rotational disk displacement (DD) of the temporomandibular joint (TMJ) and the dentoskeletal morphology. Methods: Women aged > 17 years were included in this study. Each subject had a primary complaint of malocclusion and underwent routine cephalometric examinations. They were divided into five groups according to the findings on sagittal and coronal magnetic resonance images of their TMJs: bilateral normal disk position, bilateral anterior DD with reduction (ADDR), bilateral rotational DD with reduction (RDDR), bilateral anterior DD without reduction (ADDNR), and bilateral rotational DD without reduction (RDDNR). Twenty-three cephalometric variables were analyzed, and the Kruskal-Wallis test was used to evaluate differences in the dentoskeletal morphology among the five groups. Results: Patients with TMJ DD exhibited a hyperdivergent pattern with a retrognathic mandible, unlike those with a normal disk position. These specific skeletal characteristics were more severe in patients exhibiting DD without reduction than in those with reduction, regardless of the presence of rotational DD. Rotational DD significantly influenced horizontal and vertical skeletal patterns only in the stage of DD with reduction, and the mandible exhibited a more backward position and rotation in patients with RDDR than in those with ADDR. However, there were no significant dentoskeletal differences between ADDNR and RDDNR. Conclusions: The results of this study suggest that rotational DD of TMJ plays an important role in the dentoskeletal morphology, particularly in patients showing DD with reduction.