• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.263-266
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• 1997

Three dimensional numerical model based on the finite element method(FEM) were developed to predict the mechanical behavior of hip implants. The purpose of this study is to investigate the stress distribution of two types of cementless total hip replacement femoral component -a straight stem and a curved stem, and to compare their effect on the stress shielding between two types by three dimensional finite element method. The authors analyzed von Mises stress in the cortex & stem and compared the stress between the straight and the curved stem. In comparison of stresses between two different design of femoral stem, there was 25% more decrease of stress in straight stem than curved stem in the medial cortex at proximal region. The straight stem had consistently much lower stresses than the curved stem throughout the whole medial cortex with maximum 70% reduction of stress. However, there was little change in stress between nature and 2 implanted femur throughout the lateral cortex. Stress of femoral stem was much higher in the straight stem than the curved stem up to 60%. The straight stem had more chance of stress shielding and a risk of fatigue fracture of the stem compared with the curved stem in noncement hip arthroplasty. In design of femoral stem still we have to consider to develop design to distribute more even stress on the proximal medial cortex.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.245-248
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• 1997

Excessive stress on the bone-stem interface may cause local micromotion that could produce midthigh pain, interface bone resorption and prevent bony ingrowth. It is important for clinician and prosthetic designer to develop an understanding of the load transfer mechanism, its associated stress pattern and its relationships with the particular mechanical characteristics of the femoral stem designs. Finite element method (FEM) is preeminently suited to provide information in this respect. The authors developed 3-dimensional numerical finite element models implanted with the straight stem which is composed of total 1170 elements of 8 nodes and with the curved stem which is composed of total 885 elements of 8 node, and analysed the relative micromotions between the straight stem and the curved stem in immediate postoperative stage of an uncemented total hip replacement in load simulating the single leg stance. The results showed that the rotational displacement was occupied over 90% of total micromotion in both types of stem and was peak at the proximal medial portion of the stem, but markedly less distally. The curved stem was more stable especially in terms of rotational stability. It is recommended that surgeons do not allow the patient weight bearing until bony ingrowth was achieved. In the future more attention should be drawn to increase initial rotational stability of the two types of femoral stem to prevent loosening from excessive micromotion.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.10a
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• pp.138-143
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• 2001

Based on mild slope equation and parabolic approximation the forward diffraction of monochromatic waves by a straight breakwater are studied numerically. The characteristics and effects of stem wave along breakwater and the relations between the stem wave and incident wave angle are discussed.

• Clinics in Shoulder and Elbow
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• v.21 no.2
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• pp.105-110
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• 2018

Since the introduction of shoulder arthroplasty by Neer in 1974, the design of not only the glenoid component but also the humeral component used in shoulder arthroplasty has continually evolved. Changes to the design of the humeral component include a gradually disappearing proximal fin; diversified surface finishes (such as smooth, grit-blasted, and porous coating); a more contoured stem from the originally straight and cylindrical shape; and the use of press-fit uncemented fixation as opposed to cemented fixation. Despite the evolution of the humeral component for shoulder arthroplasty, however, stem-related complications are not uncommon. Examples of stem-related complications include intraoperative humeral fractures, stem loosening, periprosthetic fractures, and stress shielding. These become much more common in revision arthroplasty, where patients are associated with further complications such as surgical difficulty in extracting the humeral component, proximal metaphyseal bone loss due to stress shielding, intraoperative humeral shaft fractures, and incomplete cement removal. Physicians have made many attempts to reduce these complications by shortening the stem of the humeral component. In this review, we will discuss some of the limitations of long-stem humeral components, the feasibility of replacing them with short-stem humeral components, and the clinical outcomes associated with short-stemmed humeral components in shoulder arthroplasty.

• Journal of radiological science and technology
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• v.43 no.6
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• pp.475-480
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• 2020

The purpose of this study was to reconstruct diffusion tensor tractography (DTT) using stem of garlic and asparagus for in vitro phantom of diffusion tensor imaging (DTI), and to compare and evaluate the fractional anisotropy (FA) value and the apparent diffusion coefficient (ADC) value to determine whether it can be used as materials for in vitro phantoms. Among various plant fibers such as stem of garlic, palmae, cotton, asparagus, etc., stem of garlic and asparagus, which are considered to be the most suitable for making phantoms, and whose shape is considered to be the most suitable for making phantoms, were selected and tests were conducted. Holes were made in a plastic bucket at an angle of 0°, 30°, 60°, 90°, and 120°, then tubes were inserted. In the tube, asparagus and stem of garlic were inserted as far in as possible, and the inserted tube was inserted into the center of the heat bathed gelatin to harden. We were able to reproduce DTT images in asparagus and stem of garlic. Fiber tissues of asparagus and stem of garlic did not show complete connectivity, but the reconstructed images of DTT showed good connectivity. The FA values of asparagus in the tubes were 0.198 at 0° (straight), 0.207 at 30°, 0.187 at 60°, 0.231 at 90°, and 0.204 at 120°. In addition, the FA values of stem of garlic in the tubes were 0.235 at 0°, 0.236 at 30°, 0.216 at 60°, 0.218 at 90°, and 0.257 at 120°. The ADC values of asparagus in the tubes were 1.545 at 0°, 1.677 at 30°, 1.629 at 60°, 1.535 at 90°, and 1.725 at 120°. In addition, the ADC values of stem of garlic in the tubes were 1.252 at 0°, 1.396 at 30°, 1.698 at 60°, 1.756 at 90°, and 1.466 at 120°. For the best expressed DTT reconstruction image, it showed the longest connectivity in the straight line as we hypothesized. In addition, when comparing the FA values and ADC values of fiber tissues of stem of garlic and asparagus, FA value was generally higher in stem of garlic and ADC value was slightly higher in asparagus.

• Journal of Plant Biology
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• v.22 no.1_2
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• pp.1-4
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• 1979

Wild soybean plants(Glycine ussuriensis) collected from Korea(47 strains) and abroad(41 strains) were grown under field condition and classified according to the growth habit. Seeds were analyzed for protein content. The results were as follows: 1. Wild soybean plants were classified into three groups each by seed size, growth habit of stem, leaf size and flowering time. 2. Seed protein was higher in the strains with large leaves, tendril, stem or late flowering. 3. Glycine gracilis, supposed to be the intermediate species between cultivated and wild soybean(according to the stem growth habit, straight or semitendril, and seed size) was medium in protein content of seeds. 4. The average protein content of Glycine ussuriensis, 43.2%, was highest in comparison with those of others such as G. gracilis, 37.5%, or G. max, 36.2%. 5. One hundred seed weight of Amphicarpaea trisperm, similar to the wild soybean, was almost same as Glycine ussuriensis, but protein content of this species was lower than wild soybeans.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.6
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• pp.539-543
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• 2006

Lodging is classified as root lodging caused by the loss of supporting force in the root, bending caused by the deformation of the stem and breaking where the stem breaks down as loads exceeding critical elasticity were applied. This research excluded breaking which is not in a state of equilibrium and tried to partition the level of lodging using an algebraic model in root lodging and stem lodging, or bending. When a vertical load was applied, the deformation of the stem of rice plant showed the form of a quadratic equation. The trace of the panicle neck in the process of lodging was an ellipse-shape. When loading was pure root lodging, the trace of the panicle neck became a circle of which culm length is the radius. When it was a pure stem lodging, the trace of the panicle neck is an ellipse of which major axis is culm length and minor axis is 0.64* culm length. When both stem lodging and root lodging occurred in a natural setting, the partitioning of lodging can be calculated by a formula using eccentricity of an ellipse, S=e*100/0.768(S is the ratio of stem lodging in the whole lodging, e is eccentricity of the ellipse). This method is expected to be useful in simple lodging partitioning. We could also calculate the partitioning of stem lodging and root lodging as units of angles as an accuracy method, by using a straight line calculated by differentiating a quadratic equation of stem deformation at the origin of the coordinates. These two methods for dividing root and stem lodging showed different values. However, each of them showed almost same values with different lodging degree in one plant.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.661-663
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• 1998

Bipolaris stem rot of cactus severely occurred up to 77% at the field of Koyang and Kimcheon from 1996 to 1997. The symptom was initially light yellow, water soaked round lesion, subsequently turned light brown and dried to death. The causal fungus was identified as Bipolaris cactivora (Petrak) Alcorn. Conidia were obclavate to fusoid, rounded ends, light brown color, 1~4 septate, and conidial size was 23~42$\times$6~9 ${\mu}{\textrm}{m}$ (av. 32.5$\times$7.5 ${\mu}{\textrm}{m}$). Conidiophores were caespitose, straight, pale to golden brown and 67~280 ${\mu}{\textrm}{m}$ in length. When healthy cacti were inoculated with the isolates obtained form the lesion of diseased plants, the same characteristic symptoms as those in the field were produced. The symptom of four-month-old cactus was developed more rapidly than that of six-month-old cactus. The pathogen was reisolated from the artificially inoculated lesions.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.2 no.1
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• pp.51-57
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• 1990

Based on second-order Stokes wave and parabolic approximation, a refraction-diffraction model for linear and nonlinear waves is developed. With the assumption that the water depth is slowly varying, the model equation describes the forward scattered wavefield. The parabolic approximation equations account for the combined effects of refraction and diffraction, while the influences of bottom friction, current and wind have been neglected. The model is tested against laboratory experiments for the case of submerged circular shoal, when both refraction and diffraction are equally significant. Based on Boussinesq equations, the parabolic approximation eq. is applied to the propagation of shallow water waves. In the case without currents, the forward diffraction of Cnoidal waves by a straight breakwater is studied numerically. The formation of stem waves along the breakwater and the relation between the stem waves and the incident wave characteristics are discussed. Numerical experiments are carried out using different bottom slopes and different angles of incidence.

• Science of Emotion and Sensibility
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• v.12 no.2
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• pp.193-204
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• 2009

The importance of corporate identity design has been recently highlighted in the marketing. However, logotype among marks that represent the image of a company has been neglected relatively comparing to symbol mark and logo mark. A logotype should be something to represent the personalities and characteristics of a company in suggestive ways. For such reasons, the image expressions by shape are thought to be important. Consequently, the formative aspects of visual communication design should be examined with emphases. However, it is true that studies on the formative aspects regarding logotypes and logo marks, especially studies on the shapes of font types and the responses of consumers to them, are lacking. Accordingly, this study examined the visual shape of logotype preferred by consumers and the shape of logotype preferred by consumers according to the business type of companies. As a result of research, there were differences in the elements of logotype preferred according to the business type of companies; as for construction companies is preferred the body of the type of dotum font with bold stem, without serif, with oblique, straight-line and curve-line endings; as for banks is preferred the body of the type of dotum font without serif, with oblique ending and with one-side curve style of serif, the stem in a middle level; as for laboratories is preferred the body of the type of dotum font with oblique ending, with bold stem and straight-line serif. The elements that should be commonly applied to construction companies, banks and laboratories appear to be the oblique ending but the curve-line ending and shallow stem seemed to be avoided. On the other hand, the serif, ending and gulim appeared to be applied differently according to the business type.