Background: Back stabilization exercises have been applied to decrease low back pain. Pilates exercise can help stabilize the low back and pelvic alignment, and uses equipment such as cadillac, reformer, chair, and barrel. Objectives: This study was conducted to confirm the effects of pilates exercise using cadillac equipment and self-exercise using back pain educational materials on pain, pelvic inclination, and single leg stance ability in adult women with back pain. Design: Randomized controlled trial. Methods: Twenty-five participants (female 25) with unspecified low back pain with lumbar hyperextension and anterior pelvic tilt were recruited. 25 adult women with back pain were randomly divided into a pilates group and a selfexercise group. Pilates exercise intervention using a cadillac was administered to the pilates group, and posture and lifestyle education materials for back pain were provided to the self-exercise group. All of the interventions were conducted 3 times a week for 4 weeks, 50 minutes per session, and the results are as follows. Results: Data analysis in each group revealed statistical differences between self-exercise and divided into a Pilates intervention. A visual analog scale (VAS)/oswestry disability index (ODI) decreased pain in both groups, Independent t-test decreased pain in both groups, but there was no significant difference. Data analysis divided into a pilates group revealed statistical differences between a VAS/ODI and pelvic tilt angle and static balance. It has been shown to increase scores or relieve pain. Conclusion: Through this study, it was confirmed that the pilates exercise using cadillac can be effectively used to reduce back pain, improve pelvic alignment, and improve single leg stance ability in adult women with low back pain.

Background: The gluteus medius (Gmed) plays a critical role in maintaining frontal plane stability of the pelvis during functional activities, such as one-leg lifting. Side-lying hip abduction (SHA) has been used as a dynamic test to evaluate Gmed function. However, the abduction force of the lower leg against the floor is not controlled during SHA. Therefore, hip abduction performance with contralateral adduction in the side-lying position (HAPCA) can be proposed as an alternative method to assess performance of hip abduction. If the number of HAPCA is related to the lateral pelvic shift distance, a new quantitative measurement for hip abductor function may be presented. Objects: This study aimed to investigate the relationship between the number of successful HAPCA and the lateral pelvic shift distance during one-leg lifting. Methods: Thirty healthy participants were recruited, and lateral pelvic shift distance was measured during one-leg lifting test using two-dimensional analysis. The number of successful HAPCA was counted when participants touched both target bars at the beat of a metronome. Results: There was a negative correlation between the number of HAPCA and lateral pelvic shift distance during one-leg lifting (r = –0.630, p < 0.05). The number of HAPCA accounted for 39.7% of the variance in the lateral pelvic shift distance during one-leg lifting (F = 18.454, p < 0.001). Conclusion: The number of successful HAPCA is significantly correlated with lateral pelvic shift distance during one-leg lifting. This finding suggests that HAPCA can be proposed as a new measurement for hip abductor performance and more research is needed on its relationship with hip abductor strength.

Background: The gluteus maximus (GM) muscle comprise the lumbo-pelvic complex and is an important stabilizing muscle during leg extension. In patients with low back pain (LBP) with weakness of the GM, spine leads to compensatory muscle activities such as instantaneous increase of the erector spinae (ES) muscle activity. Four-point kneeling arm and leg lift (FKALL) is most common types of lumbopelvic and GM muscles strengthening exercise. We assumed that altered hip position during FKALL may increase thoraco-lumbar stabilizer like GM activity more effectively method. Objects: The purpose of this study was investigated that effects of the three exercise postures on the right-sided GM, internal oblique (IO), external oblique (EO), and multifidus (MF) muscle activities and pelvic kinematic during FKALL. Methods: Twenty eight healthy individuals participated in this study. The exercises were performed three conditions of FKALL (pure FKALL, FKALL with 120° hip flexion of the supporting leg, FKALL with 30° hip abduction of the lifted leg). Participants performed FKALL exercises three times each condition, and motion sensor used to measure pelvic tilt and rotation angle. Results: This study demonstrated that no significant change in pelvic angle during hip movement in the FKALL (p > 0.05). However, the MF and GM muscle activities in FKALL with hip flexion and hip abduction is greater than pure FKALL position (p < 0.001). Conclusion: Our finding suggests that change the posture of the hip joint to facilitate GM muscle activation during trunk stabilization exercises such as the FKALL.

Background: The weakness of the gluteus medius (GM) is associated with various musculoskeletal disorders. The increasing GM activity without synergistic dominance should be considered when prescribing pelvic drop exercise (PD). Isometric hip extension or flexion of the non-weight bearing leg using thera-band at the ankle during PD may influence hip abductor activities. Objects: To determine how isometric hip extension or flexion of the non-weight bearing leg using thera-band at the ankle during PD influences the activities of three subdivisions of GM (anterior, GMa; middle, GMm; posterior, GMp), tensor fasciae latae (TFL), contralateral quadratus lumborum (QL), and GMp/TFL, GMm/QL activity ratios in patients with GM weakness. Methods: Twenty-three patients with GM weakness were recruited. Three types of PD were performed: PD, PD with an isometric hip extension of the non-weight bearing leg (PDE), and PD with an isometric hip flexion of the non-weight bearing leg (PDF). Surface electromyography (SEMG) was used to measure hip abductor activities. One-way repeated-measures analysis of variance was used to assess the statistical significance of muscle activities and muscle activity ratios. Results: GMa, GMm, and GMp activities were significantly greater during PDF than during PD and PDE (p < 0.001, p = 0.001; p = 0.001, p = 0.005; p = 0.004, p = 0.004; respectively). TFL activity was significantly greater during PDE than during PD and PDF (p < 0.001, p < 0.001, respectively). QL activity was significantly greater during PDF than during PD (p = 0.003). GMp/TFL activity ratio was significantly lower during PDE than during PD and PDF (p = 0.001, p = 0.001, respectively). There were no significant differences in the GMm/QL activity ratio. Conclusion: PDF may be an effective exercise to increase the activities of all three GM subdivisions while minimizing the TFL activity in patients with GM weakness.

Background: Excessive hamstring (HS) activation due to the weakness of the gluteus maximus (GM) causes pain in the hip joint. A single-leg deadlift is a hip extensor exercise, especially GM, that includes functional movements in daily life and complex multi-joint training. In single-leg deadlift, the muscle activity depends on the forward trunk lean angle, and it's necessary to study which muscles are used dominantly depending on the angle. Objects: The purpose of this study was to compare the effect on the muscle activity of the GM and HS during single-leg deadlift according to different forward trunk lean angles and the ratio of the GM vs HS (GM/HS). Methods: Twenty-one healthy female participants were recruited. The muscles activities of the GM, HS and the GM/HS ratio were measured through electromyography during single-leg deadlift according to three condition of forward trunk lean angles (30°, 60°, and 90°). Results: The GM and HS activities significantly differed among three conditions (p < 0.05). GM/HS ratio was significantly higher at 30°and 60° of forward trunk lean compared to 90°. Moreover, the GM activity was significantly higher at 60°of forward trunk lean than at 30° (p < 0.05). Conclusion: The single-leg deadlift at 60°of forward trunk lean is a proper GM muscle strengthening exercise.

Background: Neuromuscular electrical stimulation (NMES) is a physical modality used to activate skeletal muscles for strengthening. While voluntary muscle contraction (VMC) follows the progressive recruitment of motor units in order of size from small to large, NMES-induced muscle contraction occurs in a nonselective and synchronous pattern. Therefore, the outcome of muscle strengthening training using NMES-induced versus voluntary contraction might be different, which might affect balance performance. Objects: We examined how the NMES training affected balance and proprioception. Methods: Forty-four young adults were randomly assigned to NMES and VMC group. All participants performed one-leg standing on a force plate and sat on the Biodex (Biodex R Corp.) to measure balance and ankle proprioception, respectively. All measures were conducted before and after a training session. In NMES group, electric pads were placed on the tibialis anterior, gastrocnemius, and soleus muscles for 20 minutes. In VMC group, co-contraction of the three muscles was conducted. Outcome variables included mean distance, root mean square distance, total excursion, mean velocity, 95% confidence circle area acquired from the center of pressure data, and absolute error of dorsi/plantarflexion. Results: None of outcome variables were associated with group (p > 0.35). However, all but plantarflexion error was associated with time (p < 0.02), and the area and mean velocity were 37.0% and 18.6% lower in post than pre in NMES group, respectively, and 48.9% and 16.7% lower in post than pre in VMC group, respectively. Conclusion: Despite different physiology underlying the NMES-induced versus VMC, both training methods improved balance and ankle joint proprioception.

잭업드릴링 리그는 해양 석유와 가스 탐사 산업에서 널리 사용되는 모바일 해양 플랫폼이다. 그것은 시추 및 생산을 위한 캔틸 레버 시추 장치가 있는 독립적인 3개의 다리가 있는 자체 승강식 장치이다. 전형적인 잭업리그는 삼각형 선체, 타워형 데릭, 캔틸레버, 잭 케이스, 거주구와 다리로 구성되며 여기에는 스퍼드캔 구조, 개방형 트러스, X-교차 구조로 구성된다. 일반적으로 잭업리그는 수심 130m~170m에서만 운용이 되고 있다. 최근 들어 개발 유정이 심해로 이동하면서, 깊은 수심과 가혹한 환경조건을 만족해야 한다. 리그의 작업 상태에서 모든 정적, 동적 하중은 레그(Leg)를 통해서 지탱되는 특징이 있다. 이러한 리그의 중요한 이슈는 순간적으로 큰 충격에너 지를 발생시키는 충돌에 대한 레그의 안전성이다. 본 연구에서는 LS-Dyna 프로그램을 이용하여 DNV 선급에서 규정하고 있는 충돌에너지 35MJ 요구사항에 대한 수치해석 및 검증을 수행하였다. 충돌 선박은 배수량 7,500톤 작업 지원선을 사용하였고, 5가지 충돌조건을 선정하 였다. 해석결과로부터 모든 충돌조건은 선급 기준을 만족하지 못한다. 코드 방향 충돌조건은 충돌에너지 15MJ, 브레이스 충돌조건은 6MJ 이 합리적이다. 따라서 충돌시나리오에 따른 합리적인 충돌에너지 기준의 제정이 필요로 하다.

최근 빅데이터, 인공지능 등 눈부신 기술 발전으로 인해 자율운항선박이 현 실화되고 있으며, 산업계를 중심으로 육상에서 선박을 조종하기 위한 기술 개 발이 활발히 진행되고 있다. 이러한 자율운항선박 도입을 위한 관련 법적 검토 를 통해 국제해사협약의 필요한 개정 및 명확화 작업이 이루어질 수 있도록 함 으로써 향후 자율운항선박이 원활하게 운항될 수 있는 여건 조성에 기여할 수 있을 것이다. 이 논문에서는 11개의 법률위원회 소관협약에 한정하여 연구를 진행하였다. 우선 협약내용별 해당 조항이 자율운항선박 운용에 아무 문제없이 적용되는지, 아니면 적용되려면 개정 및 명확화 등이 필요한지 여부를 검토하 였다. LEG 협약에 대한 규정검토작업 결과, 별도의 작업이 필요하지 않거나, 일부 규정의 경우 통일해석 및 협약의 개정을 통해 자율운항선박의 운용이 가 능한 것으로 판단되었다. LEG 협약 상 도출된 주요 쟁점 사항은 정의 및 용어, 선장의 역할과 책임, 원격운항자의 역할과 책임, 법적책임, 증서, 기타사항으로 정리할 수 있다. 자율화 등급 1단계 및 2단계에서는 선박에 선원이 탑승하기 때문에, 대부분 통일해석의 개발을 통해 자율운항선박에 적용이 가능할 것으로 보인다. 선원이 승선하지 않는 자율화 등급 3단계 및 4단계에서는 현재 협약을 개정하거나 자 율운항선박에 관한 새로운 협약의 제정이 필요할 것이다. 아울러 아직 정립되 지 않은 자율운항선박, 자율화 등급 등에 대한 용어의 정의가 공통적으로 필요 하다. 그리고 선장 등에 대한 명확한 개념 및 역할도 검토가 필요하다. 일반적 으로 선장은 선박소유자를 대신하여, 선박운항 책임자로 그 역할이 상당히 중 요하다고 할 수 있다. 그러나, 자율화 등급 1단계를 제외하고 2단계, 3단계 및 4 단계에서는 선박에 선장이 승선하지 않기에 이러한 전통적인 선장의 역할 및 책임을 명확히 하는 것이 필요할 것이다. 또한, 자율운항선박 도입으로 인해 새 롭게 등장하는 원격운항자의 역할과 책임에 대한 명확화가 필요하다. LEG 협 약의 법적 검토를 통해 원격운항자 관련 부분이 상당 부분 식별되었으며, 원격 운항자의 정의, 개념, 역할 및 책임 등에 대한 부분을 명확하게 할 필요가 있다. 아울러 새로운 자율운항선박의 자율시스템 및 원격조종시스템 등이 출현하게 됨에 따라 제조업자, 시스템 개발자 등에 대한 책임 여부에 대해 명확화가 필 요하다. 그리고 항만국통제 수검을 위해 선내 비치해야 하는 보험증서를 선원 이 승선하지 않는 자율운항선박에 어떻게 처리해야하는 지에 대해 추가적인 통 일해석이나 개정이 필요할 수 있다.

Post-slaughtering storage of pork meat is important to improve the flavor and texture profile. Although irradiation of meat improves the keeping qualities of red meat, less work was done on the effect of quality in irradiated pork leg meat during post-slaughtering storage. Therefore, this study was done to compare low dosages of single beam irradiation treated pork leg meat on eating quality parameters over the nontreated meat stored at different storage temperatures. Freshly slaughter pig carcasses were brought to the irradiation unit for treatment. Pork leg meat was treated at 2 kGy with single beam. Treated (2 kGy) and non-treated pork leg meat were kept in three different temperatures as 2, 10 and 25°C for 1, 3 and 5 days and analyzed for cooking loss, shear force, color and nitrogenous flavor compounds. Cooking loss in day 5 in irradiated pork leg (30.29) was significantly lower than the control (33.27) (p<0.05). Shear force of treated (1.93) and non-treated (1.29) pork leg meat after day 5 had significant difference (p<0.05). “L*” and “b*” values of pork leg meat had significant difference at day 5 compared non treated leg meat (p<0.05) whereas the “a*” value was increased with storage time and temperature. Hypoxanthine level was significantly lower in pork leg meat at day 5 in treated (16.07) and non-treated (24.59) meats at 25°C (p<0.05) whereas the changes in AMP, IMP and Inosine was not significantly difference (p>0.05). As conclusion, post-slaughtering storage and irradiation with single beam of 2 kGy could ensure the meat quality of leg pork at even higher storage temperatures, with cooking loss, tenderness, flavor and the color which will be benefited in the processing industry.

Background: Considering the kinetic chain of the lower extremity, a pronated foot position (PFP) can affect malalignment of the lower extremity, such as a dynamic knee valgus (DKV). Although the DKV during several single-leg movement tests has been investigated, no studies have compared the differences in DKV during a single-leg step down (SLSD) between subjects with and without PFP. Objects: The purpose of this study was to compare the DKV during SLSD between subjects with and without PFP. Methods: Twelve subjects with PFP (9 men, 3 women) and 15 subjects without PFP (12 men, 3 women) participated in this study. To calculate the DKV, frontal plane projection angle (FPPA), knee-in distance (KID), and hip-out distance (HOD) during SLSD were analyzed by twodimensional video analysis software (Kinovea). Results: The FPPA was significantly lower in PFP group, compared with control group (166.4° ± 7.5° and 174.5° ± 5.5°, p < 0.05). Also, the KID was significantly greater in PFP group, compared with control group (12.7 ± 3.9 cm and 7.3 ± 2.4 cm, p < 0.05). However, the HOD not significantly differed between two groups (12.7 ± 1.7 cm and 11.4 ± 2.5 cm, p > 0.05). Conclusion: The PFP is associated with lower FPPA and greater KID. When assess the DKV during SLSD, the PFP should be considered as a crucial factor for occurrence of DKV.

This study investigated the effect of the addition of various levels of pig head meat (HM) as a substitute for rear leg meat (RLM) on the physico-chemical quality characteristics of non-emulsified, smoked, and cooked sausage during refrigerated storage. Sausages were prepared in four variations according to the proportion (0%, 10%, 20%, or 30%) of HM added and maintained at 4°C. Quality measurements were taken for 28 days. The sausages added with the addition of 20% and 30% HM had significantly (p<0.05) higher moisture and lower protein content compared to those without the addition of HM. The pH value during the storage period was higher (p<0.05) in the sausages to which the HM had been added than in those without HM. The sausages with 30% HM showed the lowest (p<0.05) L* and b* values and the highest (p<0.05) a* value during the storage period. The 2-thiobarbituric acid reactive substances (TBARS) content, hardness, cohesiveness, springiness, gumminess, and chewiness of the sausages showed no significant variations with the addition of various levels of HM. These data suggest that RLM could be substituted with 30% HM because it does not negatively affect the quality of the non-emulsified sausage. However, a further study on sausages made with 100% HM instead of RLM may be needed to improve its utilization.

Background: If there is a difference in leg length, the center of gravity shifts unilaterally toward the short leg, causing loss of balance and secondary postural imbalance, trunk muscle tone changes, gait abnormalities and pelvic imbalance. Objectives: To investigate effects of self exercise program on leg length, balance in adults with leg-length discrepancy. Design: Single blind randomized controlled trial. Methods: Twenty-eight participants were selected and divided into resistance exercise, flexibility exercise, and core exercise. Each exercise was performed for 40 minutes, 3 times a week for 6 weeks. Leg length and balance before and after exercise were measured and analyzed. Results: Following the interventions, resistance exercise group showed significant improvement in balance, but leg length difference did not show significant results. Flexibility exercise group showed significant improvement in leg length difference, but balance did not show significant results. Core exercise group showed significant improvement in leg length difference and balance. There was no significant difference in the comparison between the three groups. Conclusion: This study suggests that customized exercise according to the patient's level is beneficial to the patients.

본 연구는 외발 착지 시 신체적 특성 요인들인 발목 유연성, 성별, Q-angle이 발목 관절 상해 요인들에 미치는 영향을 분석하는데 목적이 있었다. 이를 위해 오른발을 주발로 사용하고 체육을 전공하는 20대 남성 16명(나이: 20.19±1.78 years, 체중: 69.54±10.12 kg, 신장: 173.22±4.43 cm), 여성 16명(나이: 21.05±1.53 years, 체중: 61.75±6.97 kg, 신장: 159.34±4.56 cm)을 연구대상자로 선정하였다. 외발 착지 시 신체적 특성 요인들이 발목 관절 상해에 미치는 영향을 확인하기 위하여 첫째, 발목 상해 경험에 따른 하지 관절 움직임과 관절 모멘트의 독립 t-test를 실시하였다(α = .05). 둘째, t-test를 통하여 유의한 차이를 나타낸 변인을 종속변인으로 설정하고 발목 유연성, 성별의 차이, Q-angle을 독립변인으로 지정하여 선형다중회귀분석(Multiple Linear Regression)을 사용하였다(α = .05). 본 연구결과 발목 관절 상해를 경험한 그룹은 상해를 경험하지 않은 그룹과는 다르게 발목 관절의 내전, 무릎 관절의 내측 회전을 통한 착지 전략과 기술을 사용하는 것으로 나타났다. 또한 이러한 움직임은 발목 관절의 신전 모멘트를 증가시키고, 엉덩 관절의 신전 모멘트는 감소시키는 것으로 확인되었다. 특히 발목의 배측굴곡 유연성은 발목과 무릎의 착지전략에 영향을 미치며, 성별의 차이는 발목의 신전 모멘트에 영향을 미치는 것을 알 수 있었다. 따라서 외발 착지 시 신체적 특성 요인들이 발목 관절 상해에 영향을 미치는 요인들임을 확인 할 수 있었다.

최근 해상풍력발전기 시장은 에너지 수요 증가, 화석 연료 기반 발전에 대한 의존도 감소와 환경 규제로 인해 향후 5년 내에 빠른 성장이 예상된다. 이러한 상황에 따라서 전 세계적으로 풍력 발전을 가속화하고 있으며, 해상풍력으로 진입하려는 시도가 많아지고 있다. 노르웨이 해상 안전 관리처(PSA: Petroleum Safety Authority)는 운영하는 동안 충돌사고에 대한 충돌에너지가 35 MJ을 견딜 수 있는 안전설계 기준을 요구하고 있다. 따라서 본 연구에서는 북해 해상풍력발전기 설치 단지에 투입되는 해상풍력발전기 설치 선박(WTIV)의 레그 (Leg)와 선박충돌 사고에 대하여 발생 가능한 충돌시나리오에 대해서 비선형 소성붕괴 거동 결과를 바탕으로 레그의 충돌강도평가법을 분석하였다. 분석된 결과로 현재 설계된 기존 선박을 기준으로 요구치인 35 MJ을 만족을 위해서는 200 % 이상의 단면계수 증가가 필 요하고, 이는 현실적인 레그 설계에서는 불가능한 조건으로 판단됐다. 또한, 합리적인 충돌시나리오를 기반으로 한 충돌에너지 기준의 제정이 필요하다.

본 연구는 양발 착지 시 성별에 따른 상해 경험이 무릎과 엉덩관절의 움직임 및 수직 지면반력에 미치는 영향을 분석하는데 목적이 있었다. 20대 남성 20명(상해 경험 8명, 비상해 경험 12명), 여성 20명(상해 경험 11명, 비상해 경험 9명)을 연구대상자로 선정하였다. 높이 45cm 박스에서 양발 착지를 통해 얻어진 운동역학적 변인을 Two-way mixed ANOVA를 실시하였으며, bonferroni adjustment를 이용하여 사후검증 하였다(p<.05). 본 연구결과 상해를 경험한 여성 그룹은 무릎 관절의 외반 및 내측회전 그리고 엉덩관절의 굴곡 및 외측회전 운동을 증가시켜 최대 수직 지면반발력의 감소를 유도할 수 있었던 것으로 판단된다. 상해를 경험하지 않은 여성 그룹의 경우 최대 무릎 굴곡각도가 가장 작게 나타났을 뿐만 아니라 엉덩관절의 굴곡과 외측회전 각도에서 가장 적은 수치를 나타내었고 최대 수직 지면반발력은 가장 높게 나타났다. 반면, 상해를 경험하지 않은 여성 INE 그룹의 경우 IE 그룹에 비해 상대적으로 무릎과 엉덩관절을 활용하지 못함으로서 높은 수직 지면반발력을 나타내었고, 이는 상대적으로 상해 위험성에 많이 노출되어 있음을 의미한다. 따라서 성별에 따른 상해 경험이 무릎과 엉덩관절의 운동과 최대 수직 지면반발력의 크기에 요인들에 영향을 주는 요인들임을 알 수 있었다.

Background: Uncontrolled lumbopelvic movement leads to asymmetric symptoms and causes pain in the lumbar and pelvic regions. So many patients have uncontrolled lumbopelvic movement. Passive support devices are used for unstable lumbopelvic patient. So, we need to understand that influence of passive support on lumbopelvic stability. It is important to examine that using the pelvic belt on abdominal muscle activity, pelvic rotation and pelvic tilt. Objects: This study observed abdominal muscle activity, pelvic rotation and tilt angles were compared during active straight leg raise (ASLR) with and without pelvic compression belt. Methods: Sixteen healthy women were participated in this study. ASRL with and without pelvic compression belt was performed for 5 sec, until their leg touched the target bar that was set 20 ㎝ above the base. Surface electromyography was recorded from rectus abdominis (RA), internal oblique abdominis (IO), and external oblique abdominis (EO) bilaterally. And pelvic rotation and tilt angles were measured by motion capture system. Results: There were significantly less activities of left EO (p=.042), right EO (p=.031), left IO (p=.039), right IO (p=.019), left RA (p=.044), and right RA (p=.042) and a greater right pelvic rotation angle (p=.008) and anterior pelvic tilt angle (p<.001) during ASLR with pelvic compression belt. Conclusion: These results showed that abdominal activity was reduced while the right pelvic rotation angle and anterior pelvic tilt angle were increased during ASLR with a pelvic compression belt. In other words, although pelvic compression belt could support abdominal muscle activity, it would be difficult to control pelvic movement. So pelvic belt would not be useful for controlled ASLR.