• Title/Summary/Keyword: rupture index

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Failure characteristics of combined coal-rock with different interfacial angles

  • Zhao, Tong-Bin;Guo, Wei-Yao;Lu, Cai-Ping;Zhao, Guang-Ming
    • Geomechanics and Engineering
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    • v.11 no.3
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    • pp.345-359
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    • 2016
  • In order to investigate the influence of the interfacial angel on failure characteristics and mechanism of combined coal-rock mass, 35 uniaxial/biaxial compressive simulation tests with 5 different interfacial angels of combined coal-rock samples were conducted by PFC2D software. The following conclusions are drawn: (1) The compressive strength and cohesion decrease with the increase of interfacial angle, which is defined as the angle between structure plane and the exterior normal of maximum principal plane, while the changes of elastic modulus and internal friction angle are not obvious; (2) The impact energy index $K_E$ decreases with the increase of interfacial angle, and the slip failure of the interface can be predicted based on whether the number of acoustic emission (AE) hits has multiple peaks or not; (3) There are four typical failure patterns for combined coal-rock samples including I (V-shaped shear failure of coal), II (single-fracture shear failure of coal), III (shear failure of rock and coal), and IV (slip rupture of interface); and (4) A positive correlation between interfacial angle and interface effect is shown obviously, and the interfacial angle can be divided into weak-influencing scope ($0-15^{\circ}$), moderate-influencing scope ($15-45^{\circ}$), and strong-influencing scope (> $45^{\circ}$), respectively. However, the confining pressure has a certain constraint effect on the interface effect.

Development of Self-propelled Explosive Subsoiler (1) - Present Status of Soil Compaction and Subsoil Management in Orchard - (자주식 심토환경 개선기 개발(1) - 과수원의 토양 다짐 특성 및 심토 관리 실태 -)

  • Lee, Dong-Hoon;Park, Woo-Pung;Lee, Kyou-Seung
    • Journal of Biosystems Engineering
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    • v.34 no.6
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    • pp.397-403
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    • 2009
  • This study was carried out to investigate the present status of subsoil compaction, and subsoil compaction management in orchard as a basic study for developing a self-propelled explosive subsoiler. Subsoil compaction was evaluated using the soil penetration resistance. Soil cone index was measured using the DIK 5520 type cone penetrometer in several fruit farms such as apple, pear, peach and grapes during growing seasons of these fruit in Jecheon, Gamgok, Choongju, Cheonan and Hwasung areas. Most of the subsoil managing machinery were either explosive type or digging type attached to the tractor or power tiller and turning radius of this machine was more than 3-5 m. Many of the farmers wanted to use the subsoiler which can put lime into soil and rupture soil at the same time. For most of the orchard fields, soil penetration resistance in vehicle traffic area was increased quickly and reached about 1.0 MPa in 5 cm soil depth. As the soil depth increased to 15-20 cm, cone penetration resistance reached about 2.0-2.5 MPa which restricted root growth seriously. Thus it was concluded that one of the main reason for increasing the soil compaction in orchard fields is agricultural vehicle traffic. In the vicinity of fruit trees, compaction is not so serious compared to that of the vehicle traffic area, but as the soil depth increased to 20-25 cm, in most of the orchard fields soil penetration resistance reached about 2.0-2.5 MPa which is the root growth-limiting value. Considering the rooting depth of fruit trees which ranged 30-60 cm for apple, pear and peach, and 20-30 cm for grape, it is necessary to loosen the subosoil and improve the subsoil conditions using subsoiler.

Prediction of The MOR of Larch Lumber (낙엽송 소경각재의 휨 파괴계수 예측)

  • Lee, In-Hwan;Cho, Soo-min;Hong, Soon-Il
    • Journal of the Korean Wood Science and Technology
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    • v.46 no.1
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    • pp.93-99
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    • 2018
  • It is necessary to review the non-destructive indexes in order to estimate the bending strength performance of the domestic larch lumber. In this study, MOEs (modulus of elastic) the larch lumber (cross-section $89{\times}120mm$) were evaluated through non-destructive methods such as the ultra-sonic method, longitudinal vibration method, and non-destructive bending method. The non-destructive measurement method which best represented the static MOE was determined and applied as the MOR(modulus of rupture) estimation index. The MOE that was measured through the longitudinal vibration method showed the highest correlation with the static MOE. The MOR was highly related to the static MOE. Therefore, the non-destruction MOE measured through the longitudinal vibration method was used to estimate the MOR of the lumber.

Analysis of Pediatric Tendon Injuries in the Hand in Comparison with Adults

  • Kim, Jin Sung;Sung, Seung Je;Kim, Young Joon;Choi, Young Woong
    • Archives of Plastic Surgery
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    • v.44 no.2
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    • pp.144-149
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    • 2017
  • Background The purpose of this study was to identify the epidemiologic characteristics of hand tendon injuries in children and to compare these with those of adults. Methods This retrospective study was conducted on acute traumatic tendon injuries of the hand treated at our institution from 2005 to 2013, based on medical records and X-ray findings. Age, sex, hand injured, mechanism of injury, tendons and zones injured, number of affected digits, and comorbidities and complications were analyzed. Patients were divided into 2 groups: a pediatric group (${\leq}15years$) and an adult group (>15 years). Results Over the 9-year study period, 533 patients were surgically treated for acute traumatic tendon injuries of the hand. In the pediatric group (n=76), being male, the right hand, the extensor tendon, complete rupture, the middle finger, and glass injury predominated in hand tendon injuries. In the adult group (n=457), results were similar, but injury to the index finger and knife injury were the most common. An accompanying fracture was more common in the adult group and complication rates were non-significantly different. Conclusions This comparative analysis revealed no significant epidemiologic intergroup differences. The belief that pediatric tendon injuries tend to be less severe is misplaced, and careful physical examination and exploration should be conducted in pediatric cases of hand injury.

Antibacterial Activity and Inhibition of Resistance in Methicillin-resistant Staphylococcus aureus by Maneung-hwan Ethanol Extract (만응환(萬應丸) 에탄올 추출물의 메티실린 내성 포도상구균에 대한 항균활성 및 내성억제 효과)

  • Na, Yong-su;Kim, Jong-gyu;Song, Yung-sun
    • Journal of Korean Medicine Rehabilitation
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    • v.30 no.1
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    • pp.31-45
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    • 2020
  • Objectives In this study, we investigated the antimicrobial activity of a 70% ethanol extract of Maneung-hwan (MEH), which is prescribed by practitioners of oriental medicine for use against methicillin-resistant Staphylococcus aureus (MRSA). Methods The antibacterial activity of MEH against MRSA strains was evaluated using the disc diffusion method, broth microdilution method (minimal inhibitory concentration, MIC), checkerboard dilution test, and time-kill test. The mechanism of action of MEH was investigated by bacteriolysis using detergents or ATPase inhibitors Additionally, mRNA and protein expression were investigated by quantitative reverse transcription-polymerase chain reaction and western blot assay, respectively. Results The MIC of MEH was 25~1,600 ㎍/mL against all the tested bacterial strains. We showed that MEH extract exerts strong antibacterial activity. In the checkerboard dilution test, the fractional inhibitory concentration index of MEH in combination with antibiotics indicated synergism or partial synergism against S. aureus. The time-kill study indicated that the growth of the tested bacteria was considerably inhibited after a 24-h treatment with MEH and selected antibiotics. To measure the cell membrane permeability, MEH (3.9 ㎍/mL) was combined with Triton X-100 (TX) at various concentrations N,N-dicyclohexylcarbodimide (DCCD) was also tested as an ATPase inhibitor. TX and DCCD cooperation against S. aureus exhibited synergistic action. Accordingly, the antimicrobial activity of MEH in the context of cell membrane rupture and ATPase inhibition was assessed. Additionally, the expression of genes and proteins associated with resistance was reduced after exposing MRSA to MEH. Conclusions These results suggest that MEH possesses antibacterial activity and acts as a potential natural antibiotic against MRSA.

Determining the incidence and risk factors for short-term complications following distal biceps tendon repair

  • Goedderz, Cody;Plantz, Mark A.;Gerlach, Erik B.;Arpey, Nicholas C.;Swiatek, Peter R.;Cantrell, Colin K.;Terry, Michael A.;Tjong, Vehniah K.
    • Clinics in Shoulder and Elbow
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    • v.25 no.1
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    • pp.36-41
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    • 2022
  • Background: Distal biceps rupture is a relatively uncommon injury that can significantly affect quality of life. Early complications following biceps tendon repair are not well described in the literature. This study utilizes a national surgical database to determine the incidence of and predictors for short-term complications following distal biceps tendon repair. Methods: The American College of Surgeons' National Surgical Quality Improvement Program database was used to identify patients undergoing distal biceps repair between January 1, 2011, and December 31, 2017. Patient demographic variables of sex, age, body mass index, American Society of Anesthesiologists class, functional status, and several comorbidities were collected for each patient, along with 30-day postoperative complications. Binary logistic regression was used to calculate risk ratios for these complications using patient predictor variables. Results: Early postoperative surgical complications (0.5%)-which were mostly infections (0.4%)-and medical complications (0.3%) were rare. A readmission risk factor was diabetes (risk ratio [RR], 4.238; 95% confidence interval [CI], 1.180-15.218). Non-home discharge risk factors were smoking (RR, 3.006; 95% CI, 1.123-8.044) and ≥60 years of age (RR, 4.150; 95% CI, 1.611-10.686). Maleness was protective for medical complications (RR, 0.024; 95% CI, 0.005-0.126). Surgical complication risk factors were obese class II (RR, 4.120; 95% CI, 1.123-15.120), chronic obstructive pulmonary disease (COPD; RR, 21.981; 95% CI, 3.719-129.924), and inpatient surgery (RR, 8.606; 95% CI, 2.266-32.689). Conclusions: Complication rates after distal biceps repair are low. Various patient demographics, medical comorbidities, and surgical factors were all predictive of short-term complications.

Effect of Deltoid Ligament Repair on Syndesmotic Stabilization in Patients with Ankle Fractures (발목 골절 환자에서 삼각인대봉합술이 원위경비인대결합에 미치는 영향)

  • Dae-Wook Kim;Hong Joon Choi
    • Journal of Korean Foot and Ankle Society
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    • v.27 no.2
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    • pp.58-66
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    • 2023
  • Purpose: This study aimed to evaluate the effectiveness of deltoid ligament repair on syndesmotic stabilization in patients with acute ankle fractures with ruptured deltoid and syndesmotic ligaments. Materials and Methods: The medical records of 41 patients (41 ankles) who underwent surgery for Weber type B ankle fracture with ruptured deltoid and syndesmotic ligaments were retrospectively analyzed. The mean follow-up duration was 36 months (range 18~65 months). Patients were divided into two groups: those that underwent deltoid ligament repair (the deltoid group) and those who did not (the non-deltoid group). Both groups were also divided into two subgroups, namely, the D1/S1 group, which underwent syndesmotic screw fixation, or the D2/S2 group, which did not. Medial clear space (MCS), tibiofibular clear space (TFCS), anterior fibular line (AFL) ratio, and posterior fibular line (PFL) distance were measured, and visual analog scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS), and Foot Function Index (FFI) scores were evaluated. Results: TFCS changed significantly after surgery in the D2 and S1 groups (p=0.01, p=0.03, respectively). Subgroup MCSs, TFCSs, and AFL ratios were not significantly altered by surgery in the four subgroups (p=0.82, p=0.45, p=0.25, respectively). However, postoperative PFL distances were significantly different in the D2 and S1 groups and the S1 and S2 groups (p=0.02, p=0.02, respectively). Mean TFCS decreased significantly after surgery in the D2 and S1 groups. The postoperative VAS, AOFAS scores, and FFI were not significantly different between the subgroups (p=0.44, p=0.40, and p=0.46, respectively). Conclusion: Deltoid ligament repair seemed to restore ankle stability without addressing syndesmosis in Weber type B ankle fractures with rupture of deltoid and syndesmotic ligaments.

A study on Hand Injury in Industrial Complex Workers (공단 근로자의 수부 손상에 관한 연구)

  • Kim, Soo-Min;Gu, Kyung-Sook;Lee, Geun-Hee;Kang, Ho-Hyun;Hyung, In-Han;Sung, Kwang-Jun
    • Journal of Korean Physical Therapy Science
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    • v.6 no.1
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    • pp.905-913
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    • 1999
  • The hand is a part of the body which has various functions and a sophisticated structures bone, Joint, tendon, ligament and logical nerve organ are aggregated densely in the hand of anatomy its functions are delicate. The hand's functions are very important for doing ADL and a worker's As the hand is structure which is used often and commonly it is a site that can be easily damaged by a accident on work. This study was investigated and analyzed by the results from 238 workers who had hand injury and physical therapy from January, 1997 to June, 1998 at Shin-Pung, Jang-Lim industrial complex which is located in Pusan. 1. A hand injury most frequertly happened in worker in their 30's and 20's(66 case, 28%), second was 57 case(24%) their 40's. 2. Among workers suffering from injury, who had one or less than 2 years on the job, a injury most frequently occurred. 3. Scale of workers, A injury most frequently happend in a place where had workers from 10 to 50. 99 workers from that place were 42% of total. 4. Month of occurrence rate in March were the highest compared to other months 40 injury workers in march were 17% of the total. Second was July, and the least was April that injury appeared with 10 workers. (4.2% of the total) 1. Frocture was the most common lesion 82 workers had that lesion(34%) soft tissue rupture was 71 workers who were 30% of total in type of lesion. 2. Of the site of lesion multiple case was the most common in which 57 workers had that lesion it were 24% of the total. The next was the index finger site in which 44 workers were 19% of the total. The index finger was the most common mono-site that can be lesion 36 workers were the middle finger lesion workers who were 15% of the total. Of the joint lesion, PIP was the most in which 76 workers were 44% and in MC 27 workers were 15% of the total. 3. Interval of physical therapy 79 workers from one month to 2 months, was 33% of the total and 174 workers who had therapy below 3 months were 71% 4. Post injury of disablity of the site, phalangeous disability was the most in which 148 workers had that injury and they were 62% of the total of the grade of disability 110 workers who were 46% of the total state from less than 25% disability in hand-function and 59 patients who were 25% had no disability. There were 6 workers (3% of the total) who had over -75%-dibability in the hand-function.

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Treatment of Mid-trimester Oligohydramnios Using Gami-danggui-san (임신중기(姙娠中期)에 나타난 양수과소증(oligohydramnios)에 가미당귀산(加味當歸散)을 투여하여 효과를 보인 증례보고)

  • Kim, Hyo-Jung;Kim, Eun-Seop;Jin, Dae-Hwan;Hwang, Deok-Sang;Lee, Jin-Moo;Lee, Chang-Hoon;Jang, Jun-Bock
    • The Journal of Korean Obstetrics and Gynecology
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    • v.32 no.1
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    • pp.85-93
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    • 2019
  • Objectives: The aim of this study was to demonstrate the benefit of Traditional Korean Medicine as an adjuvant therapy in management of mid-trimester oligohydramnios. Methods: It is a case report of a 31 year-old woman hospitalized for oligohydramnios at $24^{+4/7}$weeks of gestation. This patient diagnosed with special oligohydramnios had no abnormal findings such as fetal urinary abnormalities or other anomalies. Also, symptom of PPROM (preterm premature rupture of membrane) was not confirmed. The decoction, Gami-danggui-san (DG) was prescribed for the purpose of reducing unnecessary contraction of uterine muscle during pregnancy and promoting blood circulation and metabolism, thereby improving placental function and contributing to the increase of the fluid. DG decoction was administered twice a day until 19th of June, which was 10 days in total. During the treatment, level of amniotic fluid had been monitored by measuring AFI (amnioti fluid index). Results: After these conventional therapies, the amount of amniotic fluid increased steadily, and eventually reached the optimal level. AFI was found to be 3.2 on the $24^{+4/7}$ weeks, 8 on the $26^{+1/7}$ weeks, 11.5 on the $27^{+0/7}$ weeks of gestation. In the same periods, EFW (expected fetal weight) was also found to be increasing gradually: 545 g, 630, and 760 g. Conclusions: Our report implies the potential of herbal medicine as a effective therapy for oligohydramnios tratment. Further studies are needed to assess the efficacy of TKM herbal medicine and reveal the mechanisms of the decoction.

The Relationship Between the Clinical Findings and Ultrasonographic Findings of Plantar Fasciitis (족저 근막염의 임상 소견과 초음파 소견의 연관성)

  • Moon, Jeong-Seok;Bae, Woo-Han;Lee, Woo-Chun
    • The Journal of Korean Orthopaedic Ultrasound Society
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    • v.2 no.1
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    • pp.1-6
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    • 2009
  • Purpose: The goal of this study is to evaluate the relationship between the clinical findings and ultrasonographic findings of plantar fasciitis. Materials and Methods: Forty-nine symptomatic heels of 36 patients with plantar fasciitis and 21 asymptomatic heels were included. Twenty-three patients had unilateral lesions and 13 had bilateral lesions. Of these, 16 were men and 20 were women. The average age of the patients was 48.6 years. The plantar fascia thickness was measured at its insertion of the calcaneus. Qualitative parameters such as decreased echogenity, biconvexity, partial rupture and calcification of plantar fascia, and subcalcaneal spur on plain radiographs were also noted. Comparisons of ultrasonographic parameters between symptomatic heels and asymptomatic heels as well as between unilateral and bilateral groups were done. Results: There was no differences in the age, sex, body mass index, and duration of symptom between the unilateral and bilateral group. There were a statistically significant difference between the thickness of plantar fascia of unilateral group (mean 5.2 mm, SD1.5 mm) and that of bilateral group (mean 4.4 mm, SD 1.4 mm) (p=0.045). The hypoechogenity of plantar fascia and subcalcaneal spur did not differ between two groups. No fascial rupture or fascial calcification were identified. There was a statistically significant difference between the thickness of plantar fascia of symptomatic heels (mean 4.8 mm, SD1.5 mm) and that of asymptomatic heels (mean 3.1 mm, SD 0.5 mm) (p=0.000). The thickness of plantar fasia was negatively correlated with duration of symptoms (p=0.046). Conclusion: The thickness of plantar fascia in plantar fasciitis seems to be negatively correlated with the duration of symptoms, and the thickness of symptomatic heels and unilateral group was significantly thicker than that of asymptomatic heels and bilateral group, respectively.

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