본 연구의 목적은 시각정보로 양안시와 단안시 사용 시 Y-Balance Test(YBT) 수행이 YBT 절 대도달거리, 수행점수와 압력중심 변인을 통하여 동적균형에 미치는 영향을 알아보고자 하였다. 연구의 대 상자로 20-30대 성인 18명(연령: 23.17±1.72 년, 신장: 172.46±9.84 cm, 체중: 73.39±11.44 kg 다리 길이: 88.89±5.69 cm)이 연구에 참여하였다. 양안 및 단안 사용으로 동적 균형 측정을 위하여 YBT를 통 하여 절대도달거리, 종합점수, COP 변인들을 좌우발에서 측정하여 결과를 도출하였다. 연구결과로 YBT 시 후외측, 후내측, 종합점수에서 단안 차단(좌우 눈 차단)이 양안 사용보다 절대도달거리 및 종합점수가 높게 나타났다. COP 결과로, 전방 및 후내측 도달 시 차이가 나타나지 않았지만, 후외측 도달 시 전후 COP 속도에서 왼발은 단안 차단이 양안시 보다 전후 COP 속도가 느리게 나타났고, COP 속도에서 왼발 은 단안 차단이 양안시 보다 COP 속도가 느리게 나타났다.

Background: Various functional tests such as upper quarter Y-balance test (UQYBT) are used to evaluate shoulder stability and mobility in clinical or sports fields. Previous studies have been conducted to determine the correlation between the scapular or trunk muscle and UQYBT. However, the correlation between UQYBT and hip flexor, which can be considered as a core muscle, has not been confirmed. Objects: To verify the relationship between the UQYBT and scapular muscle (scapular protractor and lower trapezius [LT]), trunk muscle, and hip flexor strengths in healthy male participants. Methods: A total of 37 healthy male participants were recruited and underwent UQYBT in the push-up posture. The isometric strength of the scapular protractor, LT, trunk flexor and extensor, and hip flexors were measured using a smart KEMA strength sensor (KOREATECH Inc.). Results: The superolateral direction of the UQYBT was moderately to strongly related to trunk extensor (r = 0.443, p < 0.01), scapular protractor (r = 0.412, p < 0.05), LT (r = 0.436, p < 0.01), and both sides of the hip flexors (supporting-side: r = 0.669, p < 0.01; non-supporting- side: r = 0.641, p < 0.01). The inferolateral direction of the UQYBT was moderately related to the scapular protractor (r = 0.429, p < 0.01), LT (r = 0.511, p < 0.01), and both sides of hip flexors (supporting-side: r = 0.481, p < 0.01; non-supporting-side: r = 0.521, p < 0.01). The medial direction of the UQYBT was moderately to strongly related with the scapular protractor (r = 0.522, p < 0.01), LT (r = 0.541, p < 0.01), and both sides of hip flexors (supporting-side: r = 0.605, p < 0.01; non-supporting-side: r = 0.561, p < 0.01). Conclusion: This study showed that the strength of the scapular muscles, trunk muscles, and hip flexor muscles correlated to the UQYBT. Therefore, the strength of not only the scapular and trunk muscles but also the hip flexor muscles should be considered to improve the UQYBT.

Background: Falls are a common and serious problem in the elderly population. Muscle strength and balance are important factors in the prevention of falls. The Y-balance test (YBT) is used to assess dynamic postural control and shows excellent test-retest reliability. However, no studies have examined the relationship between lower-limb strength and YBT scores in elderly women. Objects: This study aimed to examine the relationship between lower-limb strength and YBT scores in elderly women. Methods: Thirty community-dwelling elderly women participated in the study. Lower-limb strength including hip flexor, hip extensor, hip abductor (HAB), hip adductor (HAD), knee flexor, knee extensor, ankle dorsiflexor, and ankle plantar flexor (PF) muscles was examined using a smart KEMA strength sensor (KOREATECH Inc.), and the YBT was used to assess dynamic balance. Relationship between lower-limb strength and YBT was demonstrated using a Pearson’s correlation coefficient. Results: HAB strength (r = 0.388, p < 0.05), HAD strength (r = 0.362, p < 0.05), and ankle PF strength (r = 0.391, p < 0.05) positively correlated with the YBT-anterior direction distance. Ankle PF strength was positively correlated with the YBT-posteromedial direction distance (r = 0.396, p < 0.05) and composite score (r = 0.376, p < 0.05). Conclusion: The results of this study suggest that HAB, HAD, and ankle PF strengths should be considered for dynamic postural control in elderly women.

Background: The process of language translation, adaptation, and cross-cultural validation of tools for use in multiple countries requires the adoption of well-established, comprehensive, and rigorous methodological approaches. Back translation, which is the most recommended method, permits the detection of errors in the translation and the identification of words or phrases that cannot be accurately or literally translated. Objects: The aim of this study was to verify the content validity of a Korean version of a Balance Evaluation Systems test (BESTest) by using a back-translation method. Methods: This research was conducted in six steps: 1) translation of the BESTest into Korean, 2) evaluation of the translation conformity of Korean-translated BESTest, 3) evaluation of the degree of translation comprehension, 4) back translation of Korean BESTest, 5) evaluation of the technical and conceptual equivalence, and 6) completion of the Korean version of BESTest by the translation verification committee. Results: In this study, Korean version of the BESTest achieved a rating of more than 3 (moderate) for translation comprehension, and technical equivalence and conceptual equivalence of back translation were evaluated as 3 (moderate) or more. Conclusion: The Korean version of the BESTest has proven content validity and is an appropriate tool to measure balance function.

The purpose of this study was to examine the relationship of fatigue and stress in seafarers. Ninety healthy adults were recruited and cumulative fatigue, stress index and stress resistance of seafarers were measured using autonomic nervous system analysis device (SA-6000; Medicoa Co. Ltd. Korea). The stress index had a significant correlation with the degree of resistance (p<.01). Cumulative fatigue and the stress index had a strong positive correlation (r=.781) with the stress resistance, cumulative fatigue had a strong negative correlation (r=.782) (p<0.01). Furthermore, the stress index had a strong negative correlation with the degree of resistance (r=.924) (p<.01). The present study indicate that there are significant correlation between the cumulative fatigue and stress index, cumulative fatigue and stress resistance, as well as stress index and stress resistance in the seafarers (p<.01).

Background: Assessments of Sit-to-Stand (STS) and gait functions are essential procedures in evaluating level of independence for the patients after stroke. In a previous study, we developed the software to analyze center of pressure (COP) in standing position on Wii Balance Board (WBB). Objects: This purpose of this study is to measure test-retest reliability of ground reaction forces, COP and time using WBB on STS and gait in healthy adults. Methods: Fifteen healthy participants performed three trials of STS and gait on WBB. The time (s), vertical peak (%) and COP path-length (㎝) were measured on both tasks. Additionally, counter (%), different peak (%), symmetry ratio, COP x-range and COP y-range were analyzed on STS, 1st peak (%), 2nd peak (%) of weight were analyzed on gait. Intra-class correlation coefficient (ICC), standard error measurement (SEM) and smallest real difference (SRD) were analyzed for test-retest reliability. Results: ICC of all variables except COP path-length appeared to .676∼.946 on STS, and to .723∼.901 on gait. SEM and SRD of all variables excepting COP path-length appeared .227∼8.886, .033∼24.575 on STS. SEM and SRD excepting COP path-length appeared about .019∼3.933, .054∼11.879 on gait. Conclusion: WBB is not only cheaper than force plate, but also easier to use clinically. WBB is considered as an adequate equipment for measuring changes of weight bearing during balance, STS and gait test which are normally used for functional assessment in patients with neurological problems and elderly. The further study is needed concurrent validity on neurological patients, elderly patients using force plate and WBB.

Macronutrient balance has a strong influence on fitness in insects. Previous studies have revealed that altering the concentrations of yeast and sugar in the semi-synthetic diet has a profound impact on lifespan and fecundity in Drosophila melanogaster, indicating the role of dietary protein:carbohydrate (P:C) balance in determining these two key components of fitness. However, since yeast contains not only proteins but also other macro- and micronutrients, this lifespan-determining role of dietary P:C balance needs to be corroborated using a chemically defined diet. In this study, the effects of dietary P:C balance on lifespan and fecundity were investigated in female D. melanogaster flies on one of eight isocaloric synthetic diets differing in P:C ratio (0:1, 1:16, 1:8, 1:4, 1:2, 1:1, 2:1 or 4:1). Lifespan and dietary P:C ratio were related in a convex manner, with lifespan increasing to a peak at the two intermediate P:C ratios (1:2 and 1:4) and falling at the imbalanced ratios (0:1 and 4:1). Ingesting nutritionally imbalanced diets caused flies to start ageing earlier and senesce faster. Egg production increased progressively as the dietary P:C ratio rose from 0:1 to 4:1. Long-lived flies at the intermediate P:C ratios(1:2 and 1:4) stored a greater amount of lipids than those short-lived ones at the two imbalanced ratios (0:1 and 4:1). These findings provide a strong support to the notion that dietary P:C balance is a critical determinant of lifespan and fecundity in D. melanogaster.

The purpose of this study was to examine the relationships between the ankle dorsiflexion passive range of motion (DF PROM) under a non-weight bearing condition and the normalized reach distance in three directions of the Y-Balance Test (YBT). Sixty-one healthy adults (32 males and 29 females, age: 23.0±3.0 years, height: 169.3±8.9 ㎝, weight: 61.9±5.4 ㎏) participated in this study. The ankle DF PROM was measured using a goniometer. To assess dynamic balance, all subjects performed three trials to determine the maximum lower extremity reach in the anterior, posteromedial, and posterolateral directions of the YBT. The relationship between the ankle DF PROM and both the normalized reach distance in each direction and the composite score of the YBT were analyzed using the Pearson correlation. Only the normalized reach distance in the anterior direction of the YBT was significantly related to the ankle DF PROM measured under a non-weight bearing condition (r=.50, p＜.001). Neither the normalized reach distances in the posterior directions nor the composite score of the YBT were significantly correlated with the ankle DF PROM measured under a non-weight bearing condition. These findings suggest that ankle DF PROM does not affect the overall dynamic balance of the lower extremity, with only the anterior dynamic balance affected among the three directions.

Balance is a complex motor skill that depends on interactions between multiple sensorimotor processes and environmental and functional contexts. Many rehabilitation specialists believe that balance assessment under multitask conditions may be a more sensitive indicator of balance problems and falls than balance assessment in a single-task context. Functional Gait Assessment has many tasks that allow for testing under multitask conditions. The purpose of this study was to determine the concurrent validity between the Functional Gait Assessment (FGA), Berg Balance Scale (BBS), and Timed "Up & Go" Test (TUG) in patients with stroke. One hundred and five participants with at least 3 months post stroke and able to walk at least 6 m with or without a mono cane, participated in this study. Concurrent validity between the FGA, BBS, and TUG was assessed using Spearman rank order correlation. The FGA correlated with the BBS (r=.80, p<.01) and TUG (r=-.77, p<.01). The good and moderate correlation between the FGA, BBS, and TUG establishes the concurrent validity of the FGA in patients with stroke. These measures provide clinicians with valuable information about patients' functional balance capabilities.

Steering gear is the part of an automobile that change circular movement of steering wheel to lateral movement of rack to change driving direction. This can be classified with manual and power steering gear. Manual steering gear is operated only with human power while power steering gear use oil pressure support. These days power steering gear is more common to almost of the car. Recently a korean company manufactures a speed sensitive power steering which provide variable steering feel depend on the speed of car. The Broens company of Australia produces and exports the test equipments for the manufacture of power steering valves and assemblies to major vehicle manufactures. Some korean companies imported the test equipments from Australia, thus increasing the cost. The purpose of this study is development of the valve balance test equipment to measure the valve torque of the power steering gear. This study designed and manufactured the valve balance test equipment to take hold of the power steering valve using CAE analysis. In order to evaluate the performance of the developed valve balance test equipment, the R&R tests have been conducted.

Power steering gear is the part of an automobile. That converts circular movement of steering wheel into lateral movement of rack for changing driving direction. Recently power steering gear gets more common. A Korean company manufactures a speed sensitive power steering gear, which provides variable steering feel depending on speed of the car. However, the Broens company in Australia produces and exports the test equipments for manufacturing power steering valves. Some Korean companies import the test equipments from Broens and the maintenance cost gets increasing. The purpose of this study is development of the valve balance tester to measure the valve torque of the power steering gear. This study designed and manufactured a chuck and a jig of the valve balance tester to take hold of the power steering valve using CAE analysis.

The purposes of this study were to provide the basic data and investigate the reliability of functional reach test and identify correlation of Berg balance scale (BBS) and functional reach test (FRT). The subjects were twenty healthy young adults and forty-five over 65 years old in order to compare balance ability. These data were analyzed by independent t-test and Pearson's correlation test using SPSS WIN 10.0. The results were as follows. Intrarater reliability coefficients of FRT was .976 and interrater was .942. FRT was significantly correlated with age, height, and BBS (p<.05). There were no significant differences in FRT and BBS by sex. There was significant difference in reach distance between below 74 elderly and above in FRT. FRT is very reliable test for balance and significantly correlated with BBS. Therefore, it is suggested that FRT is a clinically useful tool to substitute for BBS measuring balance ability in the elderly.

The purposes of this study were to determine correlations between the Berg Balance Test (BBS), Timed -UP & Go Test, Fugl Meyer-L/E, Balance, Sensory (FM-L/E, B, S), Motor Assessment Scale-Gait (MAS-G), Comfortable maximal Gait Speed (C MGS), and the Modified Barthel Index (MBI). The subjects were 40 stroke patients of the Korea National Rehabilitation Center in Seoul. Main outcome measures were Balance control (BBS, FM-B), Gait (TUG, C MGS, MAS-G), ADL (MBI) and Motor Function of Lower Extremities (FM-L/E, S). The data were analyzed using Pearson product correlation. FM scales between other clinical and instrumental indexes and multiple stepwise regression analyses were performed to identify prognostic factors for Balance, Gait and ADL Motor Function of Lower Extremity inclinations. The results of this study were as follows: The BBS, FM-L/E, balance, sensory and MBI showed positive correlation relations, but TUG and C MGS showed negative correlations. The sensory factor of the FM-scale showed the strongest variance in predicting BBS. However the FM-balance showed the strongest variance in predicting TUG, MAS-G and C MGS. The use of both quantitative and qualitative scales was shown to be a good measuring instrument for the classification of the general clinical performance of the patients.

This study aims to compare the relationship between the Berg Balance Scale (BBS) scores, Timed Up & Go (TUG), Functional Independent Measure (FIM), and subject characteristics. All of the 18 subjects were women between the ages of 68 and 91 (mean=80.2, SD=5.43), and they all lived at the nursing home in Wonju. Balance was measured using BBS, and functional mobility was measured using TUG. FIM was used to evaluate functional independence. Data were analyzed using Spearman correlation. Statistically significant differences were noted between BBS and TUG (r=-.486, p<.05). There were no significant statistical differences between total FIM and BBS, TUG. The FIM items "locomotion" and "communication" showed significant statistical differences between BBS and TUG. The results suggest that FIM may be able to predict dangerous falls in elderly people.