• Journal of Mechanical Science and Technology
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• v.17 no.3
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• pp.321-328
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• 2003

The elongation of contact length on the line of action is considered with particular reference for roll forming of gears, and for dynamic behavior of the tooth in meshing. However there is no paper that discuss the elongation of contact length in the load meshing of gears. Based on our investigation, the contact length on the line of action elongates more than the kinematically calculated value. In rolling, as the tool approaches the workpiece, the center distance of the gears decreases by a small amount. But, the elongation of contact length is sensitive. Therefore, the contact point on the line of action is difficult to be determined, which complicates the tooth analysis. In this study, the exact relation between the elongation of contact length and the tooth space over the recess or before the approach are revealed by experiments and kinematic theory. This analytical result applies not only for rolling, but also for the single flank meshing which is done under constant center distance.

• Journal of Trauma and Injury
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• v.30 no.2
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• pp.51-54
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• 2017

We here report a case of long-term fistula formation due to bullet retention for 30 years in the lumbar spine after a gunshot injury, and describe its treatment. A 62-year-old male visited our hospital due to pus-like discharge from his left flank. The discharge had been present for 30 years, since his recovery from an abdominal gunshot injury. A spine radiography showed radiopaque material in the body of the third lumbar vertebra. Foreign body was removed using an anterolateral retroperitoneal approach. The postoperative course was uneventful. The patient was discharged 7 days after the operation and was followed-up for 8 months, during which time, the fistula did not reoccur. A bullet retained long term in the vertebral body may cause obstinate osteomyelitis and fistula formation. A fistula caused by a foreign body in the spine can be effectively treated by surgical removal.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.5 no.3
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• pp.58-65
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• 1996

This thesis is concerned with the study on the characteristics of the cutting resistance occurring in finish machining of hardened steels such as carbon tool steel and alloy tool steel by a ceramic tool with nose radius. For the purpose, the shape of cutting cross-section made at nose part of the tool was analyzed geometrically and the wear mechanism on the flank face of the ceramic tool is investigated. In order to investigate the characteristics of cutting resistance two categories of cutting conditions are suggested, along with geometrical analysis. One category includes the conventional cutting parameters such as feed and depth of cut, another containing new cutting parameters of thickness of cut and width of cut etc. Thickness of cut width of cut and area of undeformed chip section formed by the condition of engagement between workpiece and cutting tool are determined as the function of feed, depth of cut and nose radius of cutting too, And an effective approach angle is determined by depth of cut and nose radius.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.730-734
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• 2000

Once the Chip has developed a mixed mode of side-curl and up-curl, it would generally curl to strike the too] flank. The development of the bending stresses and shear in the chip would ultimately lead to chip failure. This paper attacks this problem from a mechanics-based approach. by treating the chip as a 3-D elastic curved beam, and applying appropriate constraints and forces. The expressions for bending. shear and direct stresses are developed through an energy-based criterion. The location of the maximum stresses is also identified and explained for simulated test conditions.

• Structural Engineering and Mechanics
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• v.86 no.1
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• pp.119-137
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• 2023

The purpose of this research is to assess the performance of CBN and ceramic tools during the dry turning of gray cast iron EN GJL-350. During the turning operation, the variable machining parameters are cutting speed, feed rate, depth of cut and type of the cutting material. This contribution consists of two sections, the first one deals with the performance evaluation of four materials in terms of evolution of flank wear, surface roughness (2D and 3D) and cutting forces. The focus of the second section is on statistical analysis, followed by modeling and optimization. The experiments are conducted according to the Taguchi design L₃₂ and based on ANOVA approach to quantify the impact of input factors on the output parameters, namely, the surface roughness (Ra), the cutting force (Fz), the cutting power (Pc), specific cutting energy (Ecs). The RSM method was used to create prediction models of several technical factors (Ra, Fz, Pc, Ecs and MRR). Subsequently, the desirability function approach was used to achieve a multi-objective optimization that encompasses the output parameters simultaneously. The aim is to obtain optimal cutting regimes, following several cases of optimization often encountered in industry. The results found show that the CBN tool is the most efficient cutting material compared to the three ceramics. The optimal combination for the first case where the importance is the same for the different outputs is Vc=660 m/min, f=0.116 mm/rev, ap=0.232 mm and the material CBN. The optimization results have been verified by carrying out confirmation tests.

• Journal of Korean Neurosurgical Society
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• v.29 no.8
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• pp.1074-1079
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• 2000

We report a case of pyogenic spondylitis on L2 and L3 with diffuse epidural abscess up to T4 to L3 and large psoas abscess. A forty-nine-year old male was presented with progressive back pain, left flank pain and ab-dominal distention, weakness of the both legs and voiding and defecation difficulty during last 2 months. Initially multiple coronal hemilaminectomies from T4 to T12 were done for the treatment of diffuse thoracic epidural ab-scess. Then second operation via left retroperitoneal approach was performed for lumbar spondylitis and psoas abscess on third day after initial operation. After removal and curettage of pyogenic psoas and epidural abscess and spondylitis (L2-L3), iliac bone grafting with Keneda instrumentation from L1 to L4 was done simultaneously. Postoperative course has been unevenful without recurrent infection. The literature on diffuse epidural and large psoas abscess with pyogenic spondylitis are reviewed and instrumentation for stabilization of pyogenic spondylitis is also discussed.

• Current Optics and Photonics
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• v.1 no.6
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• pp.587-597
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• 2017

The extraction of the valid measurement region from the interference fringe pattern is a significant step when measuring gear tooth flank form deviation with grazing incidence interferometry, which will affect the measurement accuracy. In order to overcome the drawback of the conventionally used method in which the object image pattern must be captured, an improved segmentation approach is proposed in this paper. The interference fringe patterns feature, which is smoothed by the nonlinear diffusion, would be extracted by the structure tensor first. And then they are incorporated into the vector-valued Chan-Vese model to extract the valid measurement region. This method is verified in a variety of interference fringe patterns, and the segmentation results show its feasibility and accuracy.

• Journal of Korean Medical classics
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• v.36 no.3
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• pp.15-25
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• 2023

Objectives : This study aims to investigate a wide range of symptoms related to anger and their corresponding treatments as described in Traditional Korean Medical literature. Additionally, the study aims to propose key prescriptions for Intermittent Explosive Disorder(IED), thereby striving to explore potential therapeutic strategies. Methods : This comprehensive study examines the correlations between the pathologies, symptoms, and treatments related to anger, as described in the Yixuerumen (醫學入門), the Donguibogam (東醫寶鑑), and the Xiezhenglun (血證論), and their relevance to IED. Results : Anger impairs the liver, giving rise to a spectrum of symptoms including dry hair, headaches, dizziness, a bitter taste in the mouth, tinnitus, vomiting of blood, sharp chest and flank pains, abdominal discomfort, tremors, diarrhea, and hyperventilation. Furthermore, this heightened anger can serve as a potential trigger for strokes and, considering its potential to hinder recovery from various other conditions, calls for proactive therapeutic intervention. Conclusions : Severe anger has the potential to trigger strokes and hinder recovery from a range of illnesses, underscoring the necessity for tailored and proactive treatment based on the severity of symptoms. In the instance of IED, clinical application of the Danggui Luihuiwan (當歸蘆薈丸) is warranted.

• Current Optics and Photonics
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• v.7 no.4
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• pp.387-397
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• 2023

Tooth surface shape error is an important parameter in gear accuracy evaluation. When tooth surface shape error is measured by laser interferometry, the gear interferogram is highly distorted and the gray level distribution is not uniform. Therefore, it is important for gear interferometry to extract the foreground region from the gear interference fringe image directly and accurately. This paper presents an approach for foreground extraction in gear interference images by leveraging the sinusoidal variation characteristics shown by the interference fringes. A gray level mask with an adaptive threshold is established to capture the relevant features, while a local variance evaluation function is employed to analyze the fluctuation state of the interference image and derive a repair mask. By combining these masks, the foreground region is directly extracted. Comparative evaluations using qualitative and quantitative assessment methods are performed to compare the proposed algorithm with both reference results and traditional approaches. The experimental findings reveal a remarkable degree of matching between the algorithm and the reference results. As a result, this method shows great potential for widespread application in the foreground extraction of gear interference images.

• Korean Journal of Veterinary Research
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• v.45 no.4
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• pp.545-552
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• 2005

The major protocol features of the rodent uterotrophic assay have been evaluated using a range of reference chemicals. The protocol variables considered include the selection of the test species and route of chemical administration, the age of the test animals, the maintenance diet used, and the specificity of the assay for estrogens. The rodents were ovariectomized under general anesthesia via bilateral flank incisions and randomly assigned to groups of 5 animals. Chemicals were DEHP, DBP, BPA and NP, were injected sc once daily with combinations of chemicals treatments for 3 days. In the results, the reported estrogenic chemicals DEHP and DBP were both negative in the single dose treatments. But, in the combinations of chemicals treatments, DEHP and DBP increased in bud number of mammary gland. Treatment of ovariectomized mice with combinations of other chemicals resulted in uterine and vaginal hyperplasia. The additive estrogenic effects were seen with the combinations of $17{\beta}$-Bestradiol and DBP treatment. the competitive estrogenic effects were seen with the combinations of $17{\beta}$-Bestradiol and nonylphenol, $17{\beta}$-Bestradiol and bisphenol-A treatments. These results offers a sysmatic and mechanistically informative approach to assessing estrogenicity. it provides a useful profile of activity using a reasonable amount of resources and is compatible with the study of individual chemicals as well as the investigation of interactions among combinations of chemicals. The results described illustrate the intrinsic complexity of evaluating chemicals for estrogenic activities and conform the need for rigorous attention to experimental design and criteria for assessing estrogenic activity.