• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.543-549
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• 1997

The problems in the existing modeling rules for fishing nets, especially in the Tauti's rule which had been used most commonly, were investigated and it was found that the rules could not give a good similarity between the prototype and model nets because they din neither analyze the flow resistance of nets accurately nor decide the ratio of flow velocity between the two nets properly. Thus, the modeling rule was newly derived by regarding the nets as holey structures sucking water into their mouth and then filtering water through their meshes as in the previous paper. The similarity conditions obtained, between the two nets distinguished by subscript 1 and 2, are as follows; $$\frac{d_2}{d_1}=\sqrt{\frac{l_2}{l_1}},\;\frac{N_2}{N_1}=(\frac{d_1}{d_2})^{1.5}\frac{L_2}{L_1},\;\varphi_1=\varphi_2,\;\frac{d_{r2}}{d_{r1}}=\sqrt{\frac{L_2{(\rho_{r1}-\rho_{w1})}}{{L_1{(\rho_{r2}-\rho_{w2})}}$$ $$\frac{N_{a2}}{N_{a1}}=\frac{W_{a1}}{W_{a2}}(\frac{L_2}{L_1})^2,\;\nu_1=\nu_2\;and\;\frac{R_2}{R_1}=(\frac{L_2}{L_1})^2$$, where L is the length of nettings, d the diameter of netting twines, 2l the mesh size, $2\varphi$ the angle between two adjacent bars, N the number of meshes at the sides of nettings, $d_r$, the diameter of ropes, $\rho_r$, the specific gravity of ropes, $W_a$ the weight in water of one piece of float or sinker, $N_a$ the number of floats or sinkers, $\nu$ the flow velocity, and R the flow resistance of net. In the case where the model experiments aim at investigating the influence of weight in water of nettings on their shapes in nets subjected to the water flow of very low velocity, however, the following condition is added; $$\frac{\rho_2-\rho_{w2}}{\rho_1-\rho_{w1}}=\frac{d_1}{d_2}$$ where $\rho$ is the specific gravity of netting twines.

• Journal of the Korean Society of Radiology
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• v.7 no.2
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• pp.107-112
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• 2013

There is an Ankle Oblique(Broden' low) as an examination for the patient whose ankle was encased in orthopedic plaster. Some types of Ankle Joint coalition - Calcaneonavicular coalition, Talocalcaneal coalition and Naviculocuneiform coalition. This study is focused on the relation between Ankle Joints and the structural change of soft tissues, also finding the most proper angle to obtain good images of Ankle Joint from the patient who wore a plaster on his ankle, when we x-ray with Harris-Beath View($30^{\circ}{\sim}55^{\circ}$) - for observing Subtalar joint, Calcaneus Fracture, Subtentaculum, Tali Fracture and Talocalcaneal coalition. We intend to get the angle which makes us achieve the good image that shows Calcaneus Fracture, Subtentaculum, and Tali Fracture by changing internal angles of the patient's ankle. We evaluated the images obtained from 51 patients with PACS monitor. The result of the evaluation, subtalar joint was not seperated but opened, and Subtentaculum Tali Fracture was seen overlaid. at the angle 30, we could observe Calcaneus Fracture, Subtentaculum Tali Frature and the front part of behind side of subtalar joint well. And Calcaneo Navicularcoalition, Talocal Canealcoalition, Naviculo Cuneiform coalition condition were clearly seen at that angle. At the angle 35, we could achieve the clear images of subtalar comminuted fracture, talus, the behind joint of heel bone and get the high definition image on the degree of talocalcaneal joint separation. In addition to, We could obtain the good wide image of Sinus Tarsi. At the area of 45, We can distinguish the soft tissues from gyps separation. The outer-talus and density of the bone were definitely seen and Calcaneus is more separated than that of at the angle of 35, but this image is distorted. Calcaneus, Subtentaculum Tali show $1.20{\pm}0.414$ at the angle 25, $2.47{\pm}0.516$ at the angle 30, $2.27{\pm}0.458$ at the angle 45. This difference is statistically meaningful. (p<0.05). Including the degree of distortion, The distortion appears less at the area of $30^{\circ}$ but at the area of 40, there is heavy distortion. So, We could get the best image for making a diagnosis. At the $30{\sim}35^{\circ}$ degree for X-raying ankle. and at the $30{\sim}40^{\circ}$ for Calcaneus Fracture, Subtentaculum Tali Fracture.

• Journal of Korean Orthopaedic Sports Medicine
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• v.11 no.1
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• pp.44-50
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• 2012

Purpose: The purpose of this study is to analyze the relationship between acute anterior cruciate ligament (ACL) injury and bone bruise using the survey for location and incidence of bone bruise. Materials and Methods: From Jan. 2006 to Feb. 2010, 87 knees from who had complaint a traumatic knee pain were diagnosed as acute ACL tear using MRI evaluation. Associated injury, location and incidence of bone bruise were analyzed using MRI. The location of bone bruise on the MRI was classified as medial, central and lateral area on anteroposterior and lateral view of femur and tibia. The bone bruise was classified with Costa Paz classification. Results: Bone bruise of injury during daily living activity were located at medial area on coronary view and anterior area on sagittal view of distal femur, at medial area on coronary view and anterior area on sagittal view of proximal tibia (p=0.024, p=0.021, p=0.025 and p=0.029, respectively). Bone bruise of injury during sports activity were located at lateral area on coronary view and central area on sagittal view of distal femur, at lateral area on coronary view and posterior area on sagittal view of proximal tibia (p=0.014, p=0.015, p=0.018 and p=0.017, respectively). Bone bruise patterns due to traffic accident were inconclusive (p=0.264, p=0.254, p=0.229 and p=0.267, respectively). Conclusion: Injury mechanism of acute ACL injury from activities of daily living or sports activities compared to that of traffic accident showed a more consistent bone bruise patterns. Special attention to acute ACL tear must be paid in case of bone bruise at lateral tibial plateau and lateral femoral condyle.

• Journal of the Korea Concrete Institute
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• v.21 no.4
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• pp.513-521
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• 2009

Recently, the externally prestressed unbonded concrete structures are increasingly being built. The mechanical behavior of prestressed concrete beams with external unbonded tendon is different from that of normal bonded PSC beams in that the slip of tendons at deviators and the change of tendon eccentricity occurs as external loads are applied in external unbonded PSC beams. The purpose of the present paper is therefore to evaluate the flexural behavior by performing static flexural test according to tendon area and tendon force. From experimental results, before flexural cracking, there was no difference between external members and bonded members. However, after cracking, yielding load of reinforcement, ultimate load, and the tendon stress of external members was lower than that of bonded members. For the relationship of load-tendon stress, the increasing of tendon strain was inversely proportional to the initial tendon force. However, even if the initial tendon force was large, the tendon strain with small effective stress was smaller than that with large effective stress. The concrete compressive strain was proportional to the effective stress of external tendon. From the comparison between test results and codes, the ACI-318 could not consider the effect of tendon force or effective stress, and especially the results of ACI-318 were very small, so it was very conservative. And the AASHTO 1994 could be influenced on the tendon area, initial force and effective stress, but as it was made on the basis of internal unbonded tendon, its results were much larger than the test results. For this reason, the new correct predict equation of external tendon stress will be needed.

• Journal of the Korean Ceramic Society
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• v.41 no.5
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• pp.395-400
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• 2004

The effects of compositions of binders on the rheological properties of mixtures and the preparation conditions on the formation of defects and the debinding characteristics of compacts for the injection molding of ceramic powders (65 wt% aluminaㆍ35 wt% feldspar) were studied. Ceramic powders were coated with 2 wt% of stearic acid and then mixed with 15, 20, and 25 wt% of Paraffin Wax (PW) and High Density Polyethylene (HDPE) as binders at $160^{\circ}C$ for 2 h. Rheological properties were investigated by using capillary rheometer. Apparent viscosities of mixtures were 80∼300 Paㆍs at 1,000$s^{-1}$ of a shear rate, it was good for the injection molding and depending on the compositions of binders. Short shot was formed at 15H5P5 (the ratio of HDPE : PW=5 : 5 in 15 wt% of binders) compacts without injection pressures and any noticeable defects were not formed at 45 kgf/$cm^{2}$ in 20H5P5 compacts. PW and HDPE were removed by the solvent extraction and thermal debinding method. Thermal debinding of HDPE at $450^{\circ}C$ for 5 h, which followed the extraction of PW was using n-heptane solvent at $70^{\circ}C$ for 5 h. Continuous pores in compacts, which facilitate the removal of HDPE by the thermal debinding, were found to form in the compacts when PW was removed by the solvent extraction. The optimum composition of binder at which binder was removed by thermal debinding without defects while maintaining the compact strength was 20H5P5. Bulk density, porosity and 3-point bending strength of 20H5P5 compact sintered at 1,30$0^{\circ}C$ for 5 h were 2.8, < 3%, and 2,400 kgf/$cm^{2}$, respectively, and can be used as a structural materials.

• Asia pacific journal of information systems
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• v.21 no.3
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• pp.71-96
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• 2011

Within the traditional medical delivery system, patients residing in medically vulnerable areas, those with body movement difficulties, and nursing facility residents have had limited access to good healthcare services. However, Information and Communication Technology (ICT) provides us with a convenient and useful means of overcoming distance and time constraints. ICT is integrated with biomedical science and technology in a way that offers a new high-quality medical service. As a result, rapid technological advancement is expected to play a pivotal role bringing about innovation in a wide range of medical service areas, such as medical management, testing, diagnosis, and treatment; offering new and improved healthcare services; and effecting dramatic changes in current medical services. The increase in aging population and chronic diseases has caused an increase in medical expenses. In response to the increasing demand for efficient healthcare services, a telehealth service based on ICT is being emphasized on a global level. Telehealth services have been implemented especially in pilot projects and system development and technological research. With the service about to be implemented in earnest, it is necessary to study its overall acceptance by consumers, which is expected to contribute to the development and activation of a variety of services. In this sense, the study aims at positively examining the structural relationship among the acceptance factors for telehealth services based on the Technology Acceptance Model (TAM). Data were collected by showing audiovisual material on telehealth services to online panels and requesting them to respond to a structured questionnaire sheet, which is known as the information acceleration method. Among the 1,165 adult respondents, 608 valid samples were finally chosen, while the remaining were excluded because of incomplete answers or allotted time overrun. In order to test the reliability and validity of the assessment scale items, we carried out reliability and factor analyses, and in order to explore the causal relation among potential variables, we conducted a structural equation modeling analysis using AMOS 7.0 and SPSS 17.0. The research outcomes are as follows. First, service quality, innovativeness of medical technology, and social influence were shown to affect perceived ease of use and perceived usefulness of the telehealth service, which was statistically significant, and the two factors had a positive impact on willingness to accept the telehealth service. In addition, social influence had a direct, significant effect on intention to use, which is paralleled by the TAM used in previous research on technology acceptance. This shows that the research model proposed in the study effectively explains the acceptance of the telehealth service. Second, the research model reveals that information privacy concerns had a insignificant impact on perceived ease of use of the telehealth service. From this, it can be gathered that the concerns over information protection and security are reduced further due to advancements in information technology compared to the initial period in the information technology industry, and thus the improvement in quality of medical services appeared to ensure that information privacy concerns did not act as a prohibiting factor in the acceptance of the telehealth service. Thus, if other factors have an enormous impact on ease of use and usefulness, concerns over these results in the initial period of technology acceptance may become irrelevant. However, it is clear that users' information privacy concerns, as other studies have revealed, is a major factor affecting technology acceptance. Thus, caution must be exercised while interpreting the result, and further study is required on the issue. Numerous information technologies with outstanding performance and innovativeness often attract few consumers. A revised bill for those urgently in need of telehealth services is about to be approved in the national assembly. As telemedicine is implemented between doctors and patients, a wide range of systems that will improve the quality of healthcare services will be designed. In this sense, the study on the consumer acceptance of telehealth services is meaningful and offers strong academic evidence. Based on the implications, it can be expected to contribute to the activation of telehealth services. Further study is needed to assess the acceptance factors for telehealth services, such as motivation to remain healthy, health care involvement, knowledge on health, and control of health-related behavior, in order to develop unique services according to the categorization of customers based on health factors. In addition, further study may focus on various theoretical cognitive behavior models other than the TAM, such as the health belief model.

• Journal of dental hygiene science
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• v.14 no.1
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• pp.67-73
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• 2014

This study analyzed 548 pieces of these, which were reported in the Journal of Dental Hygiene Science of having been published from 2001 to Vol. 12, No. 6 in 2012. In conclusion, as for analysis of research design, first, it was the largest in cross sectional research. Second, the research subjects of survey theses were higher in order of dental hygienist and dental hygiene student. Third, number of thesis authors was the largest in order of two persons and three persons. Fourth, statistical method was in order of descriptive statistics, t-test, and ANOVA. Research theme was in order of dental health behavioral science and clinical dental hygiene. Fifth, as for research-expense benefit, only 17.7% was supported research funds. As a result of this study, there should be a research on thesis of diverse designs in the future. There is a need of being performed actively a research on alienated classer or special subjects as well as a research on activity related to dental hygiene.

• 한국해양학회지
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• v.28 no.3
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• pp.212-228
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• 1993

A chenier, about 860 m long, 30 to 60 m wide and 0.6∼1.6 m high, occurs on the upper muddy tidal flat in the Gomso bay, western coast of Korea, It consists of medium to fine sands and shells with small amounts of subangular gravels. Vertical sections across the chenier show gently landward dipping stratifications which include small-scale cross-bedded sets. the most probable source of the chenier is considered to be the intertidal sandy sediments. Vibracores taken along a line transversing the tidal flat reveal that the intertidal sand deposits are more than 5 m thick near the low-water line and become thinner toward the chenier. The most sand deposits are undertrain by tidal muds which occur behind the chenier as salt marsh deposits. C-14 age dating suggests that the sand deposits and the chenier are younger than about 1,800 years B.P. The chenier has originated from the intertidal sand shoals at the lower to mid sand flat, and has continuously moved landward. A series of aerial photographs (1967∼1989) reveal that intertidal sand shoals (predecessor of the western part of chenier) on the mid flat have continuously moved landward during the past two decades and ultimately attached to the eastern part of the chenier already anchored at the present position in the late 1960s. Repeated measurements (four times between 1991 and 1992) of morphological changes of the chenier indicate that the eastern two thirds of the chenier, mostly above the mean high water, has rarely moved whereas the western remainder below the mean high water, has moved continuously at a rate of 0.5 m/mo during the last two years (1991∼1992). This displacement rate has been considerably accelerated up to 1.0 m/mo in winter, and during a few days of typhoon in the summer of 1992 the displacement amounted to about 8∼11 m/mo for the entire chenier. these facts suggest that macro-tidal currents, coupled with winter-storm waves and infrequent strong typhoons, should play a major role for the formation and migration of chenier after 1,800 B.P., when the sea level already rose to the present position and thereafter remained constant.

• Journal of Preventive Medicine and Public Health
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• v.21 no.2 s.24
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• pp.224-237
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• 1988

To determine the causes of and related factors to childhood injuries, the emergency room records and inpatient medical records were reviewed for 4,849 injured children out of 15,790 pediatric patients(<15 years old) who visited the emergency rooms of 3 university hospitals and 2 general hospitals in Taegu from 1 January to 31 December 1987. Out of total injured children, 54.675 were 3-8 years old and the male to female ratio of the total injured children was about 2:1. The leading causes of injury were falls and slips (29.1%) and traffic accident(28.2%). The frequency of injury was higher in May-October than the rest of months and 51.6% of the injuries occurred between 15 and 20 o'clock. Falls and slips took place most frequently at the stairway(25.7%). The most common interpersonal violence was inflicted injuries(85.6%) and there were 11 child rapes. Dog bites accounted for 67.6% of all biting injuries and it occured 2.9 times more in male than in female. CO intoxication was the most common cause of poisoning (45.3%) and scalding accounted for 85.2% of all burns. Common places of drownings were river (32.2%), swimming pool (22.6%) and construction site(19.3%). To prevent childhood injuries, it is recommended to eliminate the hazardous environmental factors, to provide safe playgrounds, to educate the children for safety from kindergarten and the general public through mass communication, to establish a strict safety standard for houses, public buildings and facilities, and playgrounds.

• Journal of Korean Society of Forest Science
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• v.106 no.2
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• pp.130-149
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• 2017

The subalpine zone which is vulnerable to climate change could be functioning as a habitat for northern plant species especially in the Korean peninsula. In this study, classification of phytosociological community type and investigation on flora of vascular plants of Daecheongbong area in Mt. Seorak were carried out in order to provide a basic information for an ecological restoration and management of the vegetation through community ecological approach. Vegetation data were collected from 31 of quadrates from May to October, 2016. We analyzed vegetation types with phytosociological method, importance value with Curtis & McIntosh method, CCA using PC-ORD program tool, and flora of vascular plants. As a result, the forest vegetation was classified into Abies nephrolepis community. The community was divided 3 groups such as Pinus pumila group, Rhododendron brachycarpum group and Angelica decursiva group. Therefore, the vegetation had 3 kinds of units. The differential species group, it was classified into total of 7 species group units including Thuja koraiensis and Smilacina bicolor differential species group. The mean importance percentage (MIP) in VU 1 was shown Pinus koraiensis (24.1), A. nephrolepis (23.6) and Betula ermanii (10.5), and in VU 2, it was P. koraiensis (26.2), A. nephrolepis (20.8) and B. ermanii (10.5), and in VU 3, it was P. koraiensis (22.2), A. nephrolepis (16.4), B. ermanii (13.5) in the order, respectively. As for importance values of P. koraiensis and A. nephrolepis representative competition species, were different at each layers. The former (46.7) was higher than the latter (26.1) in tree layer, but the latter was higher than the former in subtree and, shrub and herb layers of VU 1. VU 2 and VU 3 also indicated the same tendency. P. pumila group and A. decursiva group were shown to have positive correlation with altitude and present species, respectively. The designated as the endemic plant was 11 taxa and, as the rare plant 24 taxa and 62.5% of vascular plant was northern plant species. It is necessary to continue further long-term monitoring of 3 vegetation units, IV of main competition species (P. koraiensis and A. nephrolepis) with stratum and main specific species (rare plants and endemic plants) considering vegetation science and, population and community ecology approaches.