• Title/Summary/Keyword: combined stress

Search Result 1,060, Processing Time 0.034 seconds

Assessment of Carsington Dam Failure by Slope Stability and Dam Behavior Analyses (사면안정 해석과 댐 거동분석을 통한 Carsington Dam 파괴의 고찰)

  • 송정락;김성인
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 1991.10a
    • /
    • pp.87-102
    • /
    • 1991
  • It has been reported that the failure of Carsington Dam in Eng1and occured due to the existence of a thin yellow clay layer which was not identified during the design work, and due to pre-existing shears of the clay layer. The slope stability analyses during the design work, which utilized traditional circular arc type failure method and neglected the existence of the clay layer, showed a safety factor of 1.4. However, the post-failure analyses which utilized translational failure mode considering the clay layer and the pre-existing shear deformation revealed the reduction of safety factor to unity. The post-failure analysis assumed 10。 inclination of the horizontal forces onto each slice based on the results of finite element analyses. In this paper, Bishop's simplified method, Janbu method, and Morgenstern-Price method were used for the comparison of both circular and translational failure analysis methods. The effects of the pre-existing shears and subsquent movement were also considered by varying the soil strength parameters and the pore pressure ratio according to the given soi1 parameters. The results showed factor of safefy 1.387 by Bishop's simplified method(STABL) which assumed circular arc failure surface and disregarding yellow clay layer and pre-failure material properties. Also the results showed factor of safety 1.093 by Janbu method(STABL) and 0.969 by Morgenstern-Price method(MALE) which assumed wedge failure surface and considerd yellow clay layer using post failure material properties. In addition, dam behavior was simulated by Cam-Clay model FEM program. The effects of pore pressure changes with loading and consolidation, and strength reduction near or at failure were also considered based on properly assumed stress-strain relationship and pore pressure characteristics. The results showed that the failure was initiated at the yellow clay layer and propagated through other zones by showing that stress and displacement were concentrated at the yel1ow clay layer.

  • PDF

Symbolic Analysis of a Figure Character in Satirical Cartoon 'National Intelligence Service Female Agent' (만평 속 인물캐릭터인 '국정원 여직원'의 기호적 분석)

  • Park, Keong-Cheol
    • Cartoon and Animation Studies
    • /
    • s.37
    • /
    • pp.307-334
    • /
    • 2014
  • Satirical cartoon features figure characters that liken to particular figures or social phenomenon to satirize particular figures or social phenomenon. Through the words and actions of figure characters in satirical carton, fraudulentact of man in power or irrational social phenomenon is revealed. The National Intelligence Service (NIS) female agent that is the figure character of this study has been appearing in satirical cartoon for a long time and it likens to social phenomenon instead of a actual figure. The reason why the NIS female agent has been appearing as a figure character in satirical cartoon for a long time is because related social phenomenon has not ended and is still in progress. In addition, the reason why it likens to social phenomenon instead of an actual figure is based on the fact that it is not easy to identify her face that has been hidden, which makes it difficult to exaggerate the characteristic of the figure. Her hidden face is also an expression of the desire to hide that is symbolized by baseball cap and muffler. Her hidden face and the desire to hide make it easy to substitute to other related figure or social phenomenon instead of actual figure. Namely, outward appearance of the NIS female agent has a good condition for combining 'added significance' in satirical cartoon. Irrelevant to actual NIS female agent, a satirical cartoon figure of NIS female agent is being combined with various meanings when needed and it is substituted as another figure, group or social phenomenon as the actual figure disappears. Accordingly, the purpose of this study is to reveal the role of figure character in satirical cartoon by symbolically analyzing the figure character that appears in satirical cartoon as 'NIS female agent'. The followings were revealed through the symbolic analysis of figure character in satirical cartoon in this study. First, satirical cartoon satirizes social phenomenon. Figure character in satirical cartoon satirizes social phenomenon in place of actual figure. Second, satirical cartoon satirizes core or embarrassing area of irrational social phenomenon created by politics. Figure character in satirical cartoon satirizes core or embarrassing area of social phenomenon by revealing it in place of actual figure. Third, satirical cartoon sends a message of warning to a responsible person of irrational social phenomenon created by politics. Figure character in satirical cartoon sends a message of warning to responsible person of irrational social phenomenon created by politics in place of actual figure. Fourth, satirical cartoon provides catharsis for enduring wound or stress received by individual due to irrational social phenomenon created by politics. Figure character in satirical cartoon provides catharsis for enduring wound or stress received by individual due to irrational social phenomenon through satirizing and ridiculing actual figure.

Association between Sleep Quality and Psychologic Factors among University Students in Korea (한국인 대학생에서 수면의 질과 정서적 요인에 관한 상관관계)

  • Kang, Jin-Kyu;Lim, Hyun-Dae;Lee, You-Mee
    • Journal of Oral Medicine and Pain
    • /
    • v.33 no.3
    • /
    • pp.257-267
    • /
    • 2008
  • The mentophysical disease causes diseases in digestive, respiratory, circulating systems, including chronic pain, through combined reactions from different individual characteristics, mental stress and temperamental factors. The most common symptom related to orofacial area is pain and the contributive factors include biological, behavioral, environmental, social, emotional, recognitive factors. These factors affect the course of the symptom according to individual's character and human nature. In pain, sleep acts as a contributive factor, and pain could bring about sleep disturbance and vice versa. Deterioration of sleep quality would act as a factor that aggravates mental stress. Therefore, relatively accurate and simple mental examinations and sleep quality test should be carried out for the patients with symptoms related to orofacial area. This study evaluated the mental state in relation to the sleep quality which could affect orofacial pain. The number of poor sleeper was 18 in male subjects, and 1 in female subjects and PSQI global index was higher in male($6.11{\pm}2.38$) than female($4.67{\pm}2.18$). SCL-90-R index showed no sex difference. Poor sleeper showed significantly high value in SOM, O-C, I-S, ANX, PHOB, PSY, GSI, PST. When SCL-90-R T scores were compared according to sleep quality, higher the subjective sleep quality score, O-C and I-S showed significant increase. As sleep disturbances score increased, PAR, PSY, PST showed statistically significant increase. In comparison of SCL-90-R T score according to daytime dysfunction, statistically significant increase in DEP, ANX, HOS, PHOB, PAR, GSI was observed. Therefore, the quality of sleep and psychological status have a high correlation. This is likely to influence chronic pain in the orofacial field. As a result, clinicians treating orofacial pain should evaluate the sleep quality and psychological status of the patient. Further studies of larger sample sizes including various age, occupation, and pain groups are necessary in order to apply the results to clinical practice.

Significance of tibial intra-tunnel fixation at Arthroscopic ACL Reconstruction with hamstring tendon (Second-look Arthroscopic Evalution) (자가 슬괵건을 이용한 전방 십자인대 재건술시 경골측 골 터널내 고정의 의의 (이차관절경 검사의 평가))

  • Kim, Young-Chang ;Seo, Seung-Suk;Jung, Kyung-Chil;Gwak, Hey-Chul;Kim, Yoon-Jun;Kim, Jin-Seok
    • Journal of the Korean Arthroscopy Society
    • /
    • v.10 no.2
    • /
    • pp.165-172
    • /
    • 2006
  • Purpose: The purpose of this study is to evaluate the effects of intratunnel fixation in the tibial side on the arthroscopic ACL reconstruction with quadruple hamstring tendon at the second look arthroscopy. Materials and Method: From Dec 1999 to May 2005, we arthroscopically reexamined 32 cases who had been done arthroscopic ACL reconstruction with quadruple hamstring tendons. Hamstring tendons of all cases were fixed at femoral side with RigidfixTM. At the tibial side hamstring tendons were fixed only Post-tie (Group I) or Post-tie combined with IntrafixTM (Group II). At the time of second look arthroscopy mean age of cases was 30 years and mean duration for second look arthroscopy was 21.3 months. We analyzed the results with IKDC score, KT-1000 arthrometer under anesthesia, Telos stress radiography, tibial tunnel widening on the radiography and second look arthroscopic findings. Results: Group II had more superior than group I at side to side differences with KT-1000 and Telos stress radiograph, IKDC score, but the differences were insignificant. At arthroscopic evaluation, Group ll also had more superior than group I at graft tension and graft appearance, graft synovialization, but the differences were insignificant. Tibial tunnel widening in the knee AP radiograph was 2.3 mm in Group I and 1.7 mm in Group II and the difference was significant. (P=0.042) Conclusions: Additional procedure of tibial intratunnel fixation in arthroscopic ACL reconstruction with autogenous hamstring tendon significantly prohibited from tibial tunnel widening but clinical results, radiologic joint stability, findings in second look arthroscopy were insignificantly different. We concluded that Post-tie itself induced satisfactory clinical results, joint stability and graft maturation and that tibial tunnel widening did not affect the results.

  • PDF

Effect of Glutathione S-Transferase Polymorphisms on the Antioxidant System (Glutathione S-Transferase 유전적 다형성이 항산화 체계에 미치는 영향)

  • Jeon, Gyeong-Im;Park, Eun-Ju
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.36 no.6
    • /
    • pp.708-719
    • /
    • 2007
  • Glutathione S-transferase genotypes GSTT1, GSTM1 and GSTP1 were characterized in 104 healthy male and female subjects and compared with parameters of oxidative stress at the level of DNA and lipids, with antioxidant enzymes, and with plasma antioxidants in smokers and non.smokers. Of the 104 subjects studied, 57.4% were GSTT1 present and 47.6% were GSTM1 present. The GSTP1 polymorphisms a and b were represented as follows: a/a, 75.5%; a/b, 21.6%; b/b type, 2.9%. The GSTT1 null genotype was associated with decreased glutathione in erythrocytes and elevated lymphocytes DNA damage. GST-Px was higher in GSTT1 null compared with GSTT1 present type. The homozygous GSTP1 genotype was not associated with any antioxidant status or DNA damage. The difference in plasma ${\alpha}$-carotene and erythrocytes GSH-Px and GST activities between smokers and non-smokers was detected in the GSTT1 null genotype. Plasma ${\gamma}$-tocopherol and ${\beta}$-carotene decreased significantly in smokers having GSTM1 null genotype. When GSTT1 and GSTM1 were combined, plasma lycopene and erythrocyte GST were reduced in smokers in both null types of these genes. As for GSTP1 genotype, plasma ${\alpha}$-carotene and erythrocytes GSH-Px decreased significantly in smokers with GSTP1 b/b, while erythrocytes GSH-Px activities decreased in smokers with GSTP1 a/b. The different ${\beta}$-carotene level between smokers and non-smokers was seen with both GSTP1 a/a and a/b genotype. It seems that polymorphisms in the phase II metabolizing enzyme glutathione S-transferase may be important determinants of commonly measured biomarkers.

Optimum Rheological Mixed ratio of Jumbo Squid and Alaska Pollock Surimi for Gel Product Process (대형오징어와 명태혼합 어묵의 가열겔화시 물성에 영향을 미치는 최적 혼합비)

  • LEE Nahm-Gull;YOO Seung-Geun;CHO Young-Je
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.32 no.6
    • /
    • pp.718-724
    • /
    • 1999
  • This study was investigated the changes of the properties of matter such as the gel formation of the combined fish based on the mixed rate between the ocean jumbo squid and Alaska pollock surimi, and compared the relationships between the gel formation and water holding capacity. The changes of the gel formation based on 20 min fish grinding time and $2.5\%$ salt concentration according to the mixed rate was thought as the optimal addition limit. There was no significant function of gel product more than $20\%$ Jumbo squid meat. The more squid meat in the mixed meat could make the lower breaking stress but 7:3 rate of pollock : squid could retain breaking strain. The effect of the moisture content on mixed fish meat was studied and the drastic decrease of the gel formation and water holding capacity was indicated in $78\%$.

  • PDF

The Influence of Traffic Time and Fertilizer Type on the Quality of Golf Course Putting Greens (답압시간과 비료종류가 골프코스 그린 잔디의 품질에 미치는 영향)

  • Lee, Sung-Woo;Lee, Jae-Pil;Kim, Doo-Hwan
    • Asian Journal of Turfgrass Science
    • /
    • v.22 no.1
    • /
    • pp.65-74
    • /
    • 2008
  • Traffic management is becoming an important issue in turfgrass practise on golf course. The objective of this study was to investigate the combined impact of different traffic times and types of fertilization. Traffic treatment was applied in morning (AM), noon, and afternoon (PM). Fertilizers used include faster-release fertilizer (21-17-17) and slow-release fertilizers (12-6-18, 11-3-22, 20-3-20, 10-3-10). Experiment was conducted from Oct. 1 to Nov. 30, 2005 on a nursery putting green of Incheon Grand Golf Club. The growth and quality of creeping bentgrass (Agrostis polustris cv. 'Seaside II') were evaluated on visual leaf color, leaf texture, shoot density, and root length. The measurement at 20 days after treatment, turfgrass color and leaf texture showed the best result on 10-15-10 + Noon-traffic plot. Turf quality and traffic tolerance were not different at Am and Pm traffic treatment. However, traffic stress in early morning and late evening caused the most severe damage to the turfgrass. Shoot density was the highest in 10-15-10 + Noon-traffic treatment but root length was not different among treatments after 30 day measurement. Among the fertilizers, slow release fertilizer resulted in higher turf quality and traffic tolerance than fast release fertilizer, however, shoot density did not showed a significantly different. For the fast recuperation of turfgrass from traffic injury in the early winter, it is recommended to avoid early morning and late evening traffic such as cup replacement and other maintenance practise. It is also recommended to delay the first tee-up time and ending early for last tee time during cold weather season.

Estimation of Moisture Content in Cucumber and Watermelon Seedlings Using Hyperspectral Imagery (초분광영상 이용 오이 및 수박 묘의 수분함량 추정)

  • Kim, Seong-Heon;Kang, Jeong-Gyun;Ryu, Chan-Seok;Kang, Ye-Seong;Sarkar, Tapash Kumar;Kang, Dong Hyeon;Ku, Yang-Gyu;Kim, Dong-Eok
    • Journal of Bio-Environment Control
    • /
    • v.27 no.1
    • /
    • pp.34-39
    • /
    • 2018
  • This research was conducted to estimate moisture content in cucurbitaceae seedlings, such as cucumber and watermelon, using hyperspectral imagery. Using a hyperspectral image acquisition system, the reflectance of leaf area of cucumber and watermelon seedlings was calculated after providing water stress. Then, moisture content in each seedling was measured by using a dry oven. Finally, using reflectance and moisture content, the moisture content estimation models were developed by PLSR analysis. After developing the estimation models, performance of the cucumber showed 0.73 of $R^2$, 1.45% of RMSE, and 1.58% of RE. Performance of the watermelon showed 0.66 of $R^2$, 1.06% of RMSE, and 1.14% of RE. The model performed slightly better after removing one sample from cucumber seedlings as outlier and unnecessary. Hence, the performance of new model for cucumber seedlings showed 0.79 of $R^2$, 1.10% of RMSE, and 1.20% of RE. The model performance combined with all samples showed 0.67 of $R^2$, 1.26% of RMSE, and 1.36% of RE. The model of cucumber showed better performance than the model of watermelon. This is because variables of cucumber are consisted of widely distributed variation, and it affected the performance. Further, accuracy and precision of the cucumber model were increased when an insignificant sample was eliminated from the dataset. Finally, it is considered that both models can be significantly used to estimate moisture content, as gradients of trend line are almost same and intersected. It is considered that the accuracy and precision of the estimating models possibly can be improved, if the models are constructed by using variables with widely distributed variation. The improved models will be utilized as the basis for developing low-priced sensors.

A Study on Relationship between Physical Elements and Tennis/Golf Elbow

  • Choi, Jungmin;Park, Jungwoo;Kim, Hyunseung
    • Journal of the Ergonomics Society of Korea
    • /
    • v.36 no.3
    • /
    • pp.183-196
    • /
    • 2017
  • Objective: The purpose of this research was to assess the agreement between job physical risk factor analysis by ergonomists using ergonomic methods and physical examinations made by occupational physicians on the presence of musculoskeletal disorders of the upper extremities. Background: Ergonomics is the systematic application of principles concerned with the design of devices and working conditions for enhancing human capabilities and optimizing working and living conditions. Proper ergonomic design is necessary to prevent injuries and physical and emotional stress. The major types of ergonomic injuries and incidents are cumulative trauma disorders (CTDs), acute strains, sprains, and system failures. Minimization of use of excessive force and awkward postures can help to prevent such injuries Method: Initial data were collected as part of a larger study by the University of Utah Ergonomics and Safety program field data collection teams and medical data collection teams from the Rocky Mountain Center for Occupational and Environmental Health (RMCOEH). Subjects included 173 male and female workers, 83 at Beehive Clothing (a clothing plant), 74 at Autoliv (a plant making air bags for vehicles), and 16 at Deseret Meat (a meat-processing plant). Posture and effort levels were analyzed using a software program developed at the University of Utah (Utah Ergonomic Analysis Tool). The Ergonomic Epicondylitis Model (EEM) was developed to assess the risk of epicondylitis from observable job physical factors. The model considers five job risk factors: (1) intensity of exertion, (2) forearm rotation, (3) wrist posture, (4) elbow compression, and (5) speed of work. Qualitative ratings of these physical factors were determined during video analysis. Personal variables were also investigated to study their relationship with epicondylitis. Logistic regression models were used to determine the association between risk factors and symptoms of epicondyle pain. Results: Results of this study indicate that gender, smoking status, and BMI do have an effect on the risk of epicondylitis but there is not a statistically significant relationship between EEM and epicondylitis. Conclusion: This research studied the relationship between an Ergonomic Epicondylitis Model (EEM) and the occurrence of epicondylitis. The model was not predictive for epicondylitis. However, it is clear that epicondylitis was associated with some individual risk factors such as smoking status, gender, and BMI. Based on the results, future research may discover risk factors that seem to increase the risk of epicondylitis. Application: Although this research used a combination of questionnaire, ergonomic job analysis, and medical job analysis to specifically verify risk factors related to epicondylitis, there are limitations. This research did not have a very large sample size because only 173 subjects were available for this study. Also, it was conducted in only 3 facilities, a plant making air bags for vehicles, a meat-processing plant, and a clothing plant in Utah. If working conditions in other kinds of facilities are considered, results may improve. Therefore, future research should perform analysis with additional subjects in different kinds of facilities. Repetition and duration of a task were not considered as risk factors in this research. These two factors could be associated with epicondylitis so it could be important to include these factors in future research. Psychosocial data and workplace conditions (e.g., low temperature) were also noted during data collection, and could be used to further study the prevalence of epicondylitis. Univariate analysis methods could be used for each variable of EEM. This research was performed using multivariate analysis. Therefore, it was difficult to recognize the different effect of each variable. Basically, the difference between univariate and multivariate analysis is that univariate analysis deals with one predictor variable at a time, whereas multivariate analysis deals with multiple predictor variables combined in a predetermined manner. The univariate analysis could show how each variable is associated with epicondyle pain. This may allow more appropriate weighting factors to be determined and therefore improve the performance of the EEM.

Stellite bearings for liquid Zn-/Al-Systems with advanced chemical and physical properties by Mechanical Alloying and Standard-PM-Route

  • Zoz, H.;Benz, H.U.;Huettebraeucker, K.;Furken, L.;Ren, H.;Reichardt, R.
    • Proceedings of the Korean Powder Metallurgy Institute Conference
    • /
    • 2000.04a
    • /
    • pp.9-10
    • /
    • 2000
  • An important business-field of world-wide steel-industry is the coating of thin metal-sheets with zinc, zinc-aluminum and aluminum based materials. These products mostly go into automotive industry. in particular for the car-body. into building and construction industry as well as household appliances. Due to mass-production, the processing is done in large continuously operating plants where the mostly cold-rolled metal-strip as the substrate is handled in coils up to 40 tons unwind before and rolled up again after passing the processing plant which includes cleaning, annealing, hot-dip galvanizing / aluminizing and chemical treatment. In the liquid Zn, Zn-AI, AI-Zn and AI-Si bathes a combined action of corrosion and wear under high temperature and high stress onto the transfer components (rolls) accounts for major economic losses. Most critical here are the bearing systems of these rolls operating in the liquid system. Rolls in liquid system can not be avoided as they are needed to transfer the steel-strip into and out of the crucible. Since several years, ceramic roller bearings are tested here [1.2], however, in particular due to uncontrollable Slag-impurities within the hot bath [3], slide bearings are still expected to be of a higher potential [4]. The today's state of the art is the application of slide bearings based on Stellite\ulcorneragainst Stellite which is in general a 50-60 wt% Co-matrix with incorporated Cr- and W-carbides and other composites. Indeed Stellite is used as the bearing-material as of it's chemical properties (does not go into solution), the physical properties in particular with poor lubricating properties are not satisfying at all. To increase the Sliding behavior in the bearing system, about 0.15-0.2 wt% of lead has been added into the hot-bath in the past. Due to environmental regulations. this had to be reduced dramatically_ This together with the heavily increasing production rates expressed by increased velocity of the substrate-steel-band up to 200 m/min and increased tractate power up to 10 tons in modern plants. leads to life times of the bearings of a few up to several days only. To improve this situation. the Mechanical Alloying (MA) TeChnique [5.6.7.8] is used to prOduce advanced Stellite-based bearing materials. A lubricating phase is introduced into Stellite-powder-material by MA, the composite-powder-particles are coated by High Energy Milling (HEM) in order to produce bearing-bushes of approximately 12 kg by Sintering, Liquid Phase Sintering (LPS) and Hot Isostatic Pressing (HIP). The chemical and physical behavior of samples as well as the bearing systems in the hot galvanizing / aluminizing plant are discussed. DependenCies like lubricant material and composite, LPS-binder and composite, particle shape and PM-route with respect to achievable density. (temperature--) shock-reSistibility and corrosive-wear behavior will be described. The materials are characterized by particle size analysis (laser diffraction), scanning electron microscopy and X-ray diffraction. corrosive-wear behavior is determined using a special cylinder-in-bush apparatus (CIBA) as well as field-test in real production condition. Part I of this work describes the initial testing phase where different sample materials are produced, characterized, consolidated and tested in the CIBA under a common AI-Zn-system. The results are discussed and the material-system for the large components to be produced for the field test in real production condition is decided. Outlook: Part II of this work will describe the field test in a hot-dip-galvanizing/aluminizing plant of the mechanically alloyed bearing bushes under aluminum-rich liquid metal. Alter testing, the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed. Part III of this project will describe a second initial testing phase where the won results of part 1+11 will be transferred to the AI-Si system. Part IV of this project will describe the field test in a hot-dip-aluminizing plant of the mechanically alloyed bearing bushes under aluminum liquid metal. After testing. the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed.

  • PDF