• 제목/요약/키워드: jig

검색결과 683건 처리시간 0.023초

Finite Element Analysis and Measurement on the Release of Residual Stress and Non-linear Behavior in Weldment by Mechanical Loading(I) -Finite Element Analysis-

  • Jang, K.B.;Kim, J.H.;Cho, S.M.
    • International Journal of Korean Welding Society
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    • 제2권1호
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    • pp.29-32
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    • 2002
  • In previous study, the decrease and recovery of total stiffness in welded structure was discussed on the basis of experimental examination through tensile loading and unloading test of welded specimen. The recovery of structure stiffness was caused by the release of welding residual stress through mechanical loading. In this study, analysis model that is indispensable for the effective application of MSR method was established on the basis of test and measurement result. Thermal elasto-plastic analysis for welding process was performed by non- coupled analysis. Analysis results of welding process were transfer to elasto-plastic model for tensile loading & unloading by restart technique. In elasto-plastic analysis model for mechanical loading & unloading, hardening appearance of weld metal was considered by rezoning technique and tying technique was used for JIG condition of test machine.

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베어링 내륜의 내면 연삭가공에서 진원도 개선 방안 (A scheme on roundness lmprovement in internal grinding of bearing inner race)

  • 김정석;강명창;배정철
    • 한국정밀공학회지
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    • 제13권5호
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    • pp.60-66
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    • 1996
  • Precision of bearing race is very important to maintain the clearance between ball and inner race. In internal grinding of bearing race, its roundness is dependent on shoe wear, accuracy of jig, dressing method and grinding conditions. In this study, the characteristics of shoe wear and eccentricity of workpiece were investigated experimentally. When wear of fornt shoe wear reaches at 100.mu. m and that of rear shoe reaches at 114 .mu. m, eccentricity of inner race is increased to 1.4 .mu. m. Roundness of race is mainly related to wear of rear shoe and ring type shoe is recommended to improve roundness of race.

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Kleefstra Syndrome: Review of the Literature

  • Rosie Lee;Jung Eun Moon
    • Journal of Interdisciplinary Genomics
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    • 제5권1호
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    • pp.1-4
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    • 2023
  • Kleefstra syndrome is caused by chromosome 9q34.3 deletion or heterozygous mutations in the Euchromatin Histone Methyl Transferase 1 (EHMT1) gene. The prevalence is estimated 1:25,000 to 1:35,000. Intellectual disability, distinctive facial features, hypotonia in childhood can be accompanied. The spectrum of Kleefstra syndrome includes behavioral/psychiatric problems, hearing and visual impairments, seizures, congenital heart defects, genitourinary defects, and obesity. Therefore, it is necessary to understand the pathophysiology and various manifestation of Kleefstra syndrome and discussing with a multidisciplinary team will help diagnose and treat Kleefstra syndrome patients.

β-ureidopropionase Deficiency

  • Jun Hwa Lee
    • Journal of Interdisciplinary Genomics
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    • 제5권1호
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    • pp.5-11
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    • 2023
  • β-ureidopropionase (β-UP) is an enzyme that catalyzes the final step in the pyrimidine degradation pathway, which converts β-ureidopropionate and β-ureidoisobutyrate into β-alanine and β-aminoisobutyrate, respectively. β-UP deficiency (UPB1D; OMIM # 613161) is an extremely rare autosomal recessive inborn error disease caused by a mutation in the UPB1 gene on chromosome 22q11. To date, approximately 40 cases of UPB1D have been reported worldwide, including one case in Korea. The clinical manifestations of patients with UPB1D are known to be diverse, with a very wide range of manifestations being previously reported; these manifestations include completely asymptomatic, urogenital and colorectal anomalies, or severe neurological involvement, including global developmental delay, microcephaly, early onset psychomotor retardation with dysmorphic features, epilepsy, optic atrophy, retinitis pigmentosa, severely delayed myelination, and cerebellar hypoplasia. Currently, diagnosis of UPB1D is challenging as neurological manifestations, MRI abnormalities, and biochemical analysis for pyrimidine metabolites in the urine, plasma, and cerebrospinal fluid also need to be confirmed by UPB1 gene mutations. Overall, treatment of patients with UPB1D is palliative as there is still no definitive curative treatment available.

컨테이너 임시교사의 품질개선방안 (Measures for Improving the Quality of Temporary Container Classrooms)

  • 유병재;방홍순;이종성;김옥규
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2021년도 봄 학술논문 발표대회
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    • pp.38-39
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    • 2021
  • The use of temporary container classrooms has increased in recent years due to the development of the construction industry and renovation or rehabilitation of schools. Therefore, various problems, such as errors during assembling, design and insulation issues, and noise problems, have surfaced during the construction of temporary container classrooms. This study analyzes the causes of assembly errors during the manufacturing and installation processes to improve the quality of temporary container classrooms. Assembly errors are caused by non-level planes and inaccurate cutting during the manufacturing process. In the installation process, poor leveling is a major factor that causes errors during the assembly of temporary container classrooms. These causes result in uneven horizontal or vertical planes and uneven height. To solve these problems, quality improvement measures, such as pin connection, jig, joint coupling, and surface plates are proposed in this study.

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Pseudohypoparathyroidism: Clinical Review of Diagnosis and Genetic Etiology

  • Kyung Mi Jang
    • Journal of Interdisciplinary Genomics
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    • 제5권2호
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    • pp.29-31
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    • 2023
  • Pseudohypoparathyroidism (PHP) is very rare and shows heterogeneity with impaired genetic components. PHP is characterized by parathyroid hormone resistance to target organ, related with a GNAS (guanine nucleotide-binding protein α-subunit) mutation and epimutation. PHP receptor is coupled with the stimulatory G protein which activates cyclic adenosine monophosphate formation. PHP type 1A is caused by inactivating mutations on the maternal allele of the GNAS whereas paternal allele mutations cause pseudopseudohypoparathyroidism. PHP type 1B is caused by abnormal patterns of methylation in differentially methylated region which can be divided into partial or complete. This disease has some difficulties to diagnose according to these different molecular alterations caused by complex genetic and epigenetic defects. According to this different molecular alterations, genetic confirmation must be done to discriminate their etiology.

Resistance to Thyroid Hormone Syndrome Mutation in THRB and THRA: A Review

  • Jung Eun Moon
    • Journal of Interdisciplinary Genomics
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    • 제5권2호
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    • pp.32-34
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    • 2023
  • Resistance to thyroid hormone syndrome (RTH) is a genetic disease caused by the mutation of either the thyroid hormone receptor-β (THRB) gene or the thyroid hormone receptor-α (THRA) gene. RTH caused by THRB mutations (RTH-β) is characterized by the target tissue's response to thyroid hormone, high levels of triiodothyronine and/or thyroxine, and inappropriate secretion of thyroid-stimulating hormone (TSH). THRA mutation is characterized by hypothyroidism that affects gastrointestinal, neurological, skeletal, and myocardial functions. Most patients do not require treatment, and some patients may benefit from medication therapy. These syndromes are characterized by decreased tissue sensitivity to thyroid hormones, generating various clinical manifestations. Thus, clinical changes of resistance to thyroid hormones must be recognized and differentiated, and an approach to the practice of personalized medicine through an interdisciplinary approach is needed.

KBG Syndrome: Review of the Literature

  • Jisun Park;Ji Eun Lee
    • Journal of Interdisciplinary Genomics
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    • 제5권2호
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    • pp.13-17
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    • 2023
  • KBG syndrome (KBGS) is a multisystem disorder characterized by short stature, distinctive facial features including macrodontia of upper central permanent incisors, and developmental/cognitive delay. It is caused by variants or deletion of Ankyrin Repeat Domain 11 (ANKRD11) located in chromosome 16q24.3. Since its initial report in 1975, KBG syndrome has been recognized as an exceedingly rare disorder. However, recent advancements in genetic diagnostic techniques have led to an increase in both the diagnosis rate and the number of reported cases, contributing to a rapid increase in its global prevalence. We review the clinical aspects of KBGS, including previously reported and newly reported cases, as well as the related genetic patterns discovered so far.

Deletion or Duplication Syndromes of Chromosome 22: Review

  • Kyung Ran Jun
    • Journal of Interdisciplinary Genomics
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    • 제6권1호
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    • pp.1-5
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    • 2024
  • Chromosome 22 is an acrocentric chromosome containing 500-600 genes, representing 1.5%-2% of the total DNA in cells. It was the first human chromosome to be fully sequenced by the Human Genome Project. Several syndromes involving the partial deletion or duplication of chromosome 22 are well descibed, including 22q11.2 deletion syndrome, 22q11.2 duplication syndrome, 22q11.2 distal deletion syndrome, Phelan-McDermid syndrome caused by a 22q13 deletion or pathogenic variant in SHANK3, and cat-eye syndrome caused by a 22 pter-q11 duplication. This review aims to provide concise information on the clinical characteristics of these syndromes. In particular, the similarities in features among these syndromes, genetic basis, and standard detection techniques are described, providing guidance for diagnosis and genetic counselling.

A Study on Long-Term Cycling Performance by External Pressure Change for Pouch-Type Lithium Metal Batteries

  • Seong-Ju Sim;Bong-Soo Jin;Jun-Ho Park;Hyun-Soo Kim
    • Journal of Electrochemical Science and Technology
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    • 제15권2호
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    • pp.314-320
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    • 2024
  • Lithium dendrite formation is one of the most significant problems with lithium metal batteries. The lithium dendrite reduces the lithium metal batteries' cycling life and safety. To apply consistent external pressure to a lithium metal pouch cell, we design a press jig in this study. External pressure creates dense lithium morphology by preventing lithium dendrite formation. After 300 cycles at 1 C, the cells with the external pressure perform far better than the cells without it, with a cycling retention of 97.8%. The formation of stable lithium metal is made possible by external pressure, which also enhances safety and cyclability.