• Title/Summary/Keyword: exception analysis

Search Result 515, Processing Time 0.029 seconds

Analysis and Management of Potential Development Area Using Factor of Change from Forest to Build-up (산림의 시가지 변화요인을 통한 잠재개발지 분석 및 관리방안)

  • LEE, Ji-Yeon;LIM, No-Ol;LEE, Sung-Joo;CHO, Hyo-Jin;SUNG, Hyun-Chan;JEON, Seong-Woo
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.25 no.2
    • /
    • pp.72-87
    • /
    • 2022
  • For the sustainable development and conservation of the national land, planned development and efficient environmental conservation must be accompanied. To this end, it is possible to induce development and conservation to harmonize by deriving factors affecting development through analysis of previously developed areas and applying appropriate management measures to areas with high development pressure. In this study, the relationship between the area where the land cover changed from forest to urbanization and various social, geographical, and restrictive factors was implemented in a regression formula through logistic regression analysis, and potential development sites were analyzed for Yongin City. The factor that has the greatest impact on the analysis of potential development area is the restrict factors such as Green Belt and protected areas, and the factor with the least impact is the population density. About 148km2(52%) of Yongin-si's forests were analyzed as potential development area. Among the potential development sites, the area with excellent environmental value as a protected area and 1st grade on the Environment Conservation Value Assessment Map was derived as about 13km2. Protected areas with high development potential were riparian buffer zone and special measurement area, and areas with excellent natural scenery and river were preferred as development areas. Protected areas allow certain actions to protect individual property rights. However, there is no clear permit criteria, and the environmental impact of permits is not understood. This is identified as a factor that prevents protected areas from functioning properly. Therefore, it needs to be managed through clear exception permit criteria and environmental impact monitoring.

A Neurobehavioral Performance Assessment in Lacunar Infarction Case-control Study (열공성 뇌경색 환자-대조군에서 신경행동검사의 수행 평가)

  • Kim, Ham-Gyum;Park, Sue-Kyung;Lee, Kun-Sei;Kim, Hyeoug-Su;Kim, Wha-Sun;Chang, Soung-Hoon
    • Journal of Preventive Medicine and Public Health
    • /
    • v.36 no.3
    • /
    • pp.255-262
    • /
    • 2003
  • Objectives : We carried out tests for neurobehavior by using WHO-NCTB (neurobehavioral core test battery) and Perdue pegboard score test to identify differences between lacunar infarction cases and controls. Methods : Among the subjects who underwent MRI between February 2001 and March 2002 in a university hospital located in Seoul and who were diagnosed only as lacunar infarction without any intracranial disease, 46 patients were selected as cases (male: 21, female: 25). Controls were selected who had no cerebrovascular disease on MRI by matching age (5 years), gender, and education (2 years) in a ratio of 1:1 , Among WHO-NCTB, the following 5 tests and Perdue pegboard score test were used to categorize the study subjects: digit and symbol matching, simple reaction time, Benton visual retention, digit span, and Pursuit aiming test, Results : Among the above 6 tests of neurobehavior, lacunar infarction cases showed lower score than controls except for the simple reaction time test. As the controlling variables of multivariate analysis in the stepwise regression analysis, the followings were selected due to their significant association: age, education, BMI, gender, drinking, exercise, add systolic blood pressure. From multivariate regression analysis, there was significant difference (p<0.05) between lacunar infarction cases and controls in digit and symbol matching, Benton visual retention, digit span, pursuit aiming, and Perdue pegboard score test, but not in the score of simple reaction time test. Conclusions : We suggest that the above 5 tests for neurobehavior, with the exception of the simple reaction time test, might be used as the basis for recommendation of further treatment and other neurological tests by the earlier defection for neurological abnormality in lacunar infarction.

An Analysis of the Roles of Experience in Information System Continuance (정보시스템의 지속적 사용에서 경험의 역할에 대한 분석)

  • Lee, Woong-Kyu
    • Asia pacific journal of information systems
    • /
    • v.21 no.4
    • /
    • pp.45-62
    • /
    • 2011
  • The notion of information systems (IS) continuance has recently emerged as one of the most important research issues in the field of IS. A great deal of research has been conducted thus far on the basis of theories adapted from various disciplines including consumer behaviors and social psychology, in addition to theories regarding information technology (IT) acceptance. This previous body of knowledge provides a robust research framework that can already account for the determination of IS continuance; however, this research points to other, thus-far-unelucidated determinant factors such as habit, which were not included in traditional IT acceptance frameworks, and also re-emphasizes the importance of emotion-related constructs such as satisfaction in addition to conscious intention with rational beliefs such as usefulness. Experiences should also be considered one of the most important factors determining the characteristics of information system (IS) continuance and the features distinct from those determining IS acceptance, because more experienced users may have more opportunities for IS use, which would allow them more frequent use than would be available to less experienced or non-experienced users. Interestingly, experience has dual features that may contradictorily influence IS use. On one hand, attitudes predicated on direct experience have been shown to predict behavior better than attitudes from indirect experience or without experience; as more information is available, direct experience may render IS use a more salient behavior, and may also make IS use more accessible via memory. Therefore, experience may serve to intensify the relationship between IS use and conscious intention with evaluations, On the other hand, experience may culminate in the formation of habits: greater experience may also imply more frequent performance of the behavior, which may lead to the formation of habits, Hence, like experience, users' activation of an IS may be more dependent on habit-that is, unconscious automatic use without deliberation regarding the IS-and less dependent on conscious intentions, Furthermore, experiences can provide basic information necessary for satisfaction with the use of a specific IS, thus spurring the formation of both conscious intentions and unconscious habits, Whereas IT adoption Is a one-time decision, IS continuance may be a series of users' decisions and evaluations based on satisfaction with IS use. Moreover. habits also cannot be formed without satisfaction, even when a behavior is carried out repeatedly. Thus, experiences also play a critical role in satisfaction, as satisfaction is the consequence of direct experiences of actual behaviors. In particular, emotional experiences such as enjoyment can become as influential on IS use as are utilitarian experiences such as usefulness; this is especially true in light of the modern increase in membership-based hedonic systems - including online games, web-based social network services (SNS), blogs, and portals-all of which attempt to provide users with self-fulfilling value. Therefore, in order to understand more clearly the role of experiences in IS continuance, analysis must be conducted under a research framework that includes intentions, habits, and satisfaction, as experience may not only have duration-based moderating effects on the relationship between both intention and habit and the activation of IS use, but may also have content-based positive effects on satisfaction. This is consistent with the basic assumptions regarding the determining factors in IS continuance as suggested by Oritz de Guinea and Markus: consciousness, emotion, and habit. The principal objective of this study was to explore and assess the effects of experiences in IS continuance, with special consideration given to conscious intentions and unconscious habits, as well as satisfaction. IN service of this goal, along with a review of the relevant literature regarding the effects of experiences and habit on continuous IS use, this study suggested a research model that represents the roles of experience: its moderating role in the relationships of IS continuance with both conscious intention and unconscious habit, and its antecedent role in the development of satisfaction. For the validation of this research model. Korean university student users of 'Cyworld', one of the most influential social network services in South Korea, were surveyed, and the data were analyzed via partial least square (PLS) analysis to assess the implications of this study. In result most hypotheses in our research model were statistically supported with the exception of one. Although one hypothesis was not supported, the study's findings provide us with some important implications. First the role of experience in IS continuance differs from its role in IS acceptance. Second, the use of IS was explained by the dynamic balance between habit and intention. Third, the importance of satisfaction was confirmed from the perspective of IS continuance with experience.

A STUDY ON THE MEASUREMENT OF THE IMPLANT STABILITY USING RESONANCE FREQUENCY ANALYSIS (공진 주파수 분석법에 의한 임플랜트의 안정성 측정에 관한 연구)

  • Park Cheol;Lim Ju-Hwan;Cho In-Ho;Lim Heon-Song
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.41 no.2
    • /
    • pp.182-206
    • /
    • 2003
  • Statement of problem : Successful osseointegration of endosseous threaded implants is dependent on many factors. These may include the surface characteristics and gross geometry of implants, the quality and quantity of bone where implants are placed, and the magnitude and direction of stress in functional occlusion. Therefore clinical quantitative measurement of primary stability at placement and functional state of implant may play a role in prediction of possible clinical symptoms and the renovation of implant geometry, types and surface characteristic according to each patients conditions. Ultimately, it may increase success rate of implants. Purpose : Many available non-invasive techniques used for the clinical measurement of implant stability and osseointegration include percussion, radiography, the $Periotest^{(R)}$, Dental Fine $Tester^{(R)}$ and so on. There is, however, relatively little research undertaken to standardize quantitative measurement of stability of implant and osseointegration due to the various clinical applications performed by each individual operator. Therefore, in order to develop non-invasive experimental method to measure stability of implant quantitatively, the resonance frequency analyzer to measure the natural frequency of specific substance was developed in the procedure of this study. Material & method : To test the stability of the resonance frequency analyzer developed in this study, following methods and materials were used : 1) In-vitro study: the implant was placed in both epoxy resin of which physical properties are similar to the bone stiffness of human and fresh cow rib bone specimen. Then the resonance frequency values of them were measured and analyzed. In an attempt to test the reliability of the data gathered with the resonance frequency analyzer, comparative analysis with the data from the Periotest was conducted. 2) In-vivo study: the implants were inserted into the tibiae of 10 New Zealand rabbits and the resonance frequency value of them with connected abutments at healing time are measured immediately after insertion and gauged every 4 weeks for 16 weeks. Results : Results from these studies were such as follows : The same length implants placed in Hot Melt showed the repetitive resonance frequency values. As the length of abutment increased, the resonance frequency value changed significantly (p<0.01). As the thickness of transducer increased in order of 0.5, 1.0 and 2.0 mm, the resonance frequency value significantly increased (p<0.05). The implants placed in PL-2 and epoxy resin with different exposure degree resulted in the increase of resonance frequency value as the exposure degree of implants and the length of abutment decreased. In comparative experiment based on physical properties, as the thickness of transducer increased, the resonance frequency value increased significantly(p<0.01). As the stiffness of substances where implants were placed increased, and the effective length of implants decreased, the resonance frequencies value increased significantly (p<0.05). In the experiment with cow rib bone specimen, the increase of the length of abutment resulted in significant difference between the results from resonance frequency analyzer and the $Periotest^{(R)}$. There was no difference with significant meaning in the comparison based on the direction of measurement between the resonance frequency value and the $Periotest^{(R)}$ value (p<0.05). In-vivo experiment resulted in repetitive patternes of resonance frequency. As the time elapsed, the resonance frequency value increased significantly with the exception of 4th and 8th week (p<0.05). Conclusion : The development of resonance frequency analyzer is an attempt to standardize the quantitative measurement of stability of implant and osseointegration and compensate for the reliability of data from other non-invasive measuring devices It is considered that further research is needed to improve the efficiency of clinical application of resonance frequency analyzer. In addition, further investigation is warranted on the standardized quantitative analysis of the stability of implant.

The Framework of Research Network and Performance Evaluation on Personal Information Security: Social Network Analysis Perspective (개인정보보호 분야의 연구자 네트워크와 성과 평가 프레임워크: 소셜 네트워크 분석을 중심으로)

  • Kim, Minsu;Choi, Jaewon;Kim, Hyun Jin
    • Journal of Intelligence and Information Systems
    • /
    • v.20 no.1
    • /
    • pp.177-193
    • /
    • 2014
  • Over the past decade, there has been a rapid diffusion of electronic commerce and a rising number of interconnected networks, resulting in an escalation of security threats and privacy concerns. Electronic commerce has a built-in trade-off between the necessity of providing at least some personal information to consummate an online transaction, and the risk of negative consequences from providing such information. More recently, the frequent disclosure of private information has raised concerns about privacy and its impacts. This has motivated researchers in various fields to explore information privacy issues to address these concerns. Accordingly, the necessity for information privacy policies and technologies for collecting and storing data, and information privacy research in various fields such as medicine, computer science, business, and statistics has increased. The occurrence of various information security accidents have made finding experts in the information security field an important issue. Objective measures for finding such experts are required, as it is currently rather subjective. Based on social network analysis, this paper focused on a framework to evaluate the process of finding experts in the information security field. We collected data from the National Discovery for Science Leaders (NDSL) database, initially collecting about 2000 papers covering the period between 2005 and 2013. Outliers and the data of irrelevant papers were dropped, leaving 784 papers to test the suggested hypotheses. The co-authorship network data for co-author relationship, publisher, affiliation, and so on were analyzed using social network measures including centrality and structural hole. The results of our model estimation are as follows. With the exception of Hypothesis 3, which deals with the relationship between eigenvector centrality and performance, all of our hypotheses were supported. In line with our hypothesis, degree centrality (H1) was supported with its positive influence on the researchers' publishing performance (p<0.001). This finding indicates that as the degree of cooperation increased, the more the publishing performance of researchers increased. In addition, closeness centrality (H2) was also positively associated with researchers' publishing performance (p<0.001), suggesting that, as the efficiency of information acquisition increased, the more the researchers' publishing performance increased. This paper identified the difference in publishing performance among researchers. The analysis can be used to identify core experts and evaluate their performance in the information privacy research field. The co-authorship network for information privacy can aid in understanding the deep relationships among researchers. In addition, extracting characteristics of publishers and affiliations, this paper suggested an understanding of the social network measures and their potential for finding experts in the information privacy field. Social concerns about securing the objectivity of experts have increased, because experts in the information privacy field frequently participate in political consultation, and business education support and evaluation. In terms of practical implications, this research suggests an objective framework for experts in the information privacy field, and is useful for people who are in charge of managing research human resources. This study has some limitations, providing opportunities and suggestions for future research. Presenting the difference in information diffusion according to media and proximity presents difficulties for the generalization of the theory due to the small sample size. Therefore, further studies could consider an increased sample size and media diversity, the difference in information diffusion according to the media type, and information proximity could be explored in more detail. Moreover, previous network research has commonly observed a causal relationship between the independent and dependent variable (Kadushin, 2012). In this study, degree centrality as an independent variable might have causal relationship with performance as a dependent variable. However, in the case of network analysis research, network indices could be computed after the network relationship is created. An annual analysis could help mitigate this limitation.

Association between Critical Thinking Disposition and Grade Point Average Score in Dental Hygiene Students (치위생(학)과 학생의 학업성적에 따른 비판적 사고 성향)

  • Hwang, Hye-Rim;Kim, Eung-Kwon;Cho, Young-Sik
    • Journal of dental hygiene science
    • /
    • v.12 no.1
    • /
    • pp.7-13
    • /
    • 2012
  • Critical thinking is a essential competency for dental hygiene education and practice. The purpose of this study was to examine critical thinking disposition between groups classified by GPA score in two dental hygiene educational program. A total 252 dental hygiene students responded. The study extracted six dimensions(intellectual eagerness/curiosity, prudence, healthy skepticism, intellectual integrity, objectivity, self-confidence) derived from 27 items with the exception of systematicity using factor analysis. The mean score for critical thinking disposition was 3.47 on a 5 point scale. The result showed a statistically significant correlation critical thinking disposition and age. Multivariate analysis of covariance(MANCOVA) was used to compare six subscales between the three groups. MANCOVA results revealed that intellectual eagerness/curiosity for three groups were significantly different(Wilks's lamda=0.914, F(6, 24)=1.869), p=0.01, partial eta square=0.044). Multiple comparison for intellectual eagerness/curiosity by Scheffe's method showed differences between high score group and mid score group(p=0.027), high score group and low score group(p=0.002). In this study, academic achievement and critical thinking tends to show significant correlations is known. Critical thinking skills by examining the actual grade compares the difference in propensity scores according to a case study in intellectual curiosity, passion, and could tell the difference to appear.

Estimation on Optimum Fishing Effort of Walleye Pollock Fishery in the East Coast of Korea : Based on the Economic Analysis between Danish Seine Fishery and Trawl Fishery for Walleye Pollock (한국 동해 명태 어업의 적정어획노력량 추정 -동해구기선저인망어업과 동해구트롤어업의 경제성분석을 근거로-)

  • 이장욱
    • The Journal of Fisheries Business Administration
    • /
    • v.22 no.2
    • /
    • pp.75-99
    • /
    • 1991
  • A quantitative analysis was carried out to monitor the commercial yield level of walleye pollock Theragra chalcogramma in the east coast of Korea, based on available data on catch and fishing effort, catch per unit of effort including fish prices from 1911 to 1988, using a traditional yield model. The results from the quantitative assessment were based to estimate maximum economic yield (MEY) and optimal fishing effort (E-opt) at MEY. On the other hand, interaction aspects between danish seine fishery and trawl fishery mainly targeting walleye pollock in the east coast of Korea were studied to predict optimal situation in fishing effort level from economic point of view which gives the most benefits to the two fisheries. Total production of walleye pollock in 1911 when its catch record was begun for the first time was about 12, 000 metric tons(M/T), and then the catch trend maintained nearly at the level of 50, 000 M/T per annum, showing a decreasing trend until 1930. The highest production from historical data base on walleye pollock fishery statistics was from the years in 1939 and 1940, about 270, 000 M/T and 26, 000 M/T, respectively. No production of the fish species was recorded during the years from 1943 to 1947, and from 1949 to 1951. From 1952 onwards annual production was only available from the southern part of 38$^{\circ}$N in the east coast. During two decades from 1952 to 1970, the production had sustained about less than 30, 000 M/T every year. Annual production showed an increasing trend from 1971, reaching a maximum level of approximately 162, 000 M/T in 1981. Afterwards, it has deceased sharply year after year and amounted to 180, 000 M/T in 1988. The catch composition of walleye pollock for different fishery segments during 1970~1988 showed that more than 70% of the total catch was from danish seine fishery until 1977 but from 1978 onwards, the catch proportion did not differ from one another, accounting for the nearly same proportion. Catch per unit of effort (CPUE) for both danish seine fishery and trawl fishery maintained a decline tendency after 1977 when the values of CPUE were at level of 800 kg/haul for the former fishery and 1, 300 kg/haul for the latter fishery, respectively. CPUEs of gillnet fishery during 1980~1983 increased to about 3.5 times as high value as in the years, 1970~1979 and during 1987~1988 it decreased again to the level of the years, 1970~1978. The bottom longline fishery's CPUE wa at a very low level (20 kg/basket) through the whole study years, with exception of the value (60 kg/basket) in 1980. Fishing grounds of walleye pollock in the east coast of Korea showed a very limited distribution range. Danish seine fishery concentrated fishing around the coastal areas of Sokcho and Jumunjin during January~February and October~December. Distributions of fishing grounds of trawl fishery were the areas along the coastal regions in the central part of the east coast. Gillnet and bottom longline fisheries fished walleye pollock mainly in the areas of around Sokcho and Jumunjin during January~February and December. Relationship between CPUEs' values from danish seine fishery and trawl fishery was used to standardize fishing effort to apply to surplus production model for estimating maximum sustainable yield (MSY) and optimum fish effort (F-opt) at MSY. The results suggested a MSY of 114, 000 M/T with an estimated F-opt of 173, 000 hauls per year. Based on the estimates of MSY and F-opt, MEY was estimated to be about 94, 000 M/T with a range of 81, 000 to 103, 000 M/T and E-opt 100, 000 hauls per year with a range of 80, 000 to 120, 000 hauls. The estimated values of MEY and E-opt corresponded to 82% of MSY and 58% of F-opt, respectively. An optimal situation in the fishing effort level, which can envisage either simultaneously maximum yield or maximum benefit for both danish seine fishery and trawl fishery, was determined from relationship between revenue and cost of running the fleet : the optimal fishing effort of danish seine fishery was about 52, 000 hauls per year, corresponding to 50 danish seiners and 27, 000 hauls per year which is equal nearly to 36 trawlers, respectively. It was anticipated that the net income from sustainable yield estimated from the respective optimal fishing effort of the two fisheries will be about 3, 800 million won for danish seine fishery and 1, 000 million won for trawl fishery.

  • PDF

Studies of Long-term Variability of Methane in the Moo-Ahn Observatory Site in Korea (무안지역을 중심으로 한 메탄의 장주기적 농도변화 특성 연구)

  • Choi, Gyoo-Hoon;Youn, Yong-Hoon;Kang, Chang-Hee;Jo, Young-Min;Ko, Eui-Jang;Kim, Ki-Hyun
    • Journal of the Korean earth science society
    • /
    • v.23 no.3
    • /
    • pp.280-293
    • /
    • 2002
  • In this study, we analyzed the long-term distribution patterns of $CH_4$ determined from the Moo-Ahn (MAN) observatory in relation with those derived from the world major background monitoring sites. Comparison of the data were made using those data sets collected for the period between Aug. 1995 to Dec. 1991. The mean $CH_4$ concentration of MAN observatory was measured to be 1898${\pm}$85.3 ppb, recording the highest concentration of all the monitoring sites. When the concentration of $CH_4$ for different stations was compared over latitudinal scale, its concentration appeared to increase systematically as a function of latitude with an exception of MAN (and the other Korean monitoring site at Tae Ahn). Moreover, such phenomenon was more distinctive in Northern than Southern Hemisphere. According to the analysis of the monthly distribution patterns of $CH_4$ at MAN observatory, its concentration level began to increase from the months of February/March and peaked during August. In addition, when the level of oscillation in monthly concentrations (between the maximum and minimum values) was checked, differences were significant between MAN and other monitoring stations. If the rate of concentration change was checked using the data sets collected for this limited time period in terms of linear regression analysis, results for MAN showed the highest annual increasing rate of 16.5 ppb. It is hence suggested that the largest variability in the $CH_4$ distribution patterns at MAN observatory may be reflected by the high irregularity in its source/sink processes.

Discussion on the Strategic Priorities and Navy's Coping in the Interwar Period Britain, 1919?1939 (「전간기 영국의 전략 우선순위 논의와 영국해군의 대응, 1919-1939」)

  • Jeon, Yoon-Jae
    • Strategy21
    • /
    • s.32
    • /
    • pp.123-159
    • /
    • 2013
  • The purpose of this research paper is to re-valuate the factors that affected the Royal Navy's rearmament and preparation for war by conducting analysis on the discussion held in the Britain on the strategic priorities and Navy's coping measures adopted during the interwar period. After the end of the WWI, each of the military arms of the Britain faced significant difficulty in securing budget and increasing their military power all throughout the interwar period, and the Navy was not an exception. The WWII that got started on September 1939 was the turning point in which this difficulty led to full-fledged crisis. Immensely many criticisms followed after the war and problems were identified when it comes to the Royal Navy's performance during the war. This type of effort to identify problem led to the attempt to analyze whether Royal Navy's preparation for war and rearmament policy during interwar period were adequate, and to identify the root causes of failure. Existing studies sought to find the root cause of failed rearmament from external factors such as the deterioration of the Britain itself or pressure from the Treasury Department to cut the budget for national defense, or sought to detect problems from the development of wrong strategies by the Navy. However, Royal Navy's failed preparation for the war during interwar period is not the result of one or two separate factors. Instead, it resulted due to the diverse factors and situations that the Britain was facing at the time, and due to intricate and complex interaction of these factors. Meanwhile, this research paper focused on the context characterized by 'strategic selection and setting up of priorities' among the various factors to conduct analysis on the Navy's rearmament by linking it with the discussion held at the time on setting up strategic priorities, and sought to demonstrate that the Navy Department's inadequate counter-measures developed during this process waned Royal Navy's position. After the end of WWI, each of the military arms continued to compete for the limited resources and budget all throughout the interwar period, and this type of competition amidst the situation in which the economic situation of Britain was still unstable, made prioritization when it comes to the allocation of resources and setting up of the priorities when it comes to the military power build-up, inevitable. Amidst this situation, the RAF was able to secure resources first and foremost, encouraged by the conviction of some politicians who were affected by the 'theory of aerial threat' and who believed that curtailing potential attack with the Air Force would be means to secure national security at comparatively lower cost. In response, Navy successfully defended the need for the existence of Navy despite the advancement of the aerial power, by emphasizing that the Britain's livelihood depends on trade and on the maintenance of maritime traffic. Despite this counter-measuring logic, however, Navy's role was still limited to the defense of overseas territory and to the fleet run-off instead of sea traffic route production when it comes to the specific power build-up plan, and did not understand the situation in which financial and economic factors gained greater importance when it comes to the setting up of strategic priorities. As a result, Navy's plan to build its powers was met with continual resistance of the Treasury Department, and lost the opportunity to re-gain the status of 'senior service' that it had enjoyed in the past during the competition for strategic prioritization. Given that the strategic and economic situation that Korea faces today is not very different from that of the Britain during the interwar period, our Navy too should leverage the lessons learned from the Royal Navy to make the effort to secure viable position when it comes to the setting of priorities in case of national defense strategy by presenting the basis on why maritime coping should be prioritized among the numerous other threats, and by developing the measures for securing the powers needed effectively amidst the limited resources.

  • PDF

Analysis of the Lower Extremity's Coupling Angles During Forward and Backward Running (앞으로 달리기와 뒤로 달리기 시 하지 커플링각 분석)

  • Ryu, Ji-Seon
    • Korean Journal of Applied Biomechanics
    • /
    • v.16 no.3
    • /
    • pp.149-163
    • /
    • 2006
  • The purpose of this study was to compare the lower extremity's joint and segment coupling patterns between forward and backward running in subjects who were twelve healthy males. Three-dimensional kinematic data were collected with Qualisys system while subjects ran to forward and backward. The thigh internal/external rotation and tibia internal/external rotation, thigh flexion/extension and tibia flexion/extension, tibia internal/external rotation and foot inversion/eversion, knee internal/external rotation and ankle inversion/eversion, knee flexion/extension and ankle inversion/eversion, knee flexion/extension and ankle flexion/extension, and knee flexion/extension and tibia internal/external rotation coupling patterns were determined using a vector coding technique. The comparison for each coupling between forward and backward running were conducted using a dependent, two-tailed t-test at a significant level of .05 for the mean of each of five stride regions, midstance(1l-30%), toe-off(31-50%), swing acceleration(51-70%), swing deceleration(71-90), and heel-strike(91-10%), respectively. 1. The knee flexion/extension and ankle flexion/extension coupling pattern of both foreward and backward running over the stride was converged on a complete coordination. However, the ankle flexion/extension to knee flexion/extension was relatively greater at heel-strike in backward running compared with forward running. At the swing deceleration, backward running was dominantly led by the ankle flexion/extension, but forward running done by the knee flexion/extension. 2. The knee flexion/extension and ankle inversion/eversion coupling pattern for both running was also converged on a complete coordination. At the mid-stance. the ankle movement in the frontal plane was large during forward running, but the knee movement in the sagital plane was large during backward running and vice versa at the swing deceleration. 3. The knee flexion/extension and tibia internal/external rotation coupling while forward and backward run was also centered on the angle of 45 degrees, which indicate a complete coordination. However, tibia internal/external rotation dominated the knee flexion/extension at heel strike phase in forward running and vice versa in backward running. It was diametrically opposed to the swing deceleration for each running. 4. Both running was governed by the ankle movement in the frontal plane across the stride cycle within the knee internal/external rotation and tibia internal/external rotation. The knee internal/external rotation of backward running was greater than that of forward running at the swing deceleration. 5. The tibia internal/external rotation in coupling between the tibia internal/external rotation and foot inversion/eversion was relatively great compared with the foot inversion/eversion over a stride for both running. At heel strike, the tibia internal/external rotation of backward running was shown greater than that of forward(p<.05). 6. The thigh internal/external rotation took the lead for both running in the thigh internal/external rotation and tibia internal/external rotation coupling. In comparison of phase, the thigh internal/external rotation movement at the swing acceleration phase in backward running worked greater in comparison with forward running(p<.05). However, it was greater at the swing deceleration in forward running(p<.05). 7. With the exception of the swing deceleration phase in forward running, the tibia flexion/extension surpassed the thigh flexion/extension across the stride cycle in both running. Analysis of the specific stride phases revealed the forward running had greater tibia flexion/extension movement at the heel strike than backward running(p<.05). In addition, the thigh flexion/extension and tibia flexion/extension coupling displayed almost coordination at the heel strike phase in backward running. On the other hand the thigh flexion/extension of forward running at the swing deceleration phase was greater than the tibia flexion/extension, but it was opposite from backward running. In summary, coupling which were the knee flexion/extension and ankle flexion/extension, the knee flexion/extension and ankle inversion/eversion, the knee internal/external rotation and ankle inversion/eversion, the tibia internal/external rotation and foot inversion/eversion, the thigh internal/external rotation and tibia internal/external rotation, and the thigh flexion/extension and tibia flexion/extension patterns were most similar across the strike cycle in both running, but it showed that coupling patterns in the specific stride phases were different from average point of view between two running types.