• Title/Summary/Keyword: Test procedures

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Comparison of Test Standards for the Performance and Safety of Agricultural Tractors: A Review

  • Kabir, Md. Shaha Nur;Chung, Sun-Ok;Kim, Yong-Joo;Shin, Sung-Hyun
    • Journal of Biosystems Engineering
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    • v.39 no.3
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    • pp.158-165
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    • 2014
  • Purpose: The objective of this paper was to compare test standards regarding the performance and safety of agricultural tractors to identify the differences in test conditions, measurement tolerances, and test procedures. Based on the comparison, some recommendations were proposed for possible revisions or improvements to current tractor test standards. Methods: The test standards and codes of major standards development organizations (SDOs), such as the Organization for Economic Cooperation and Development (OECD), the International Organization for Standardization (ISO), the American Society of Agricultural and Biological Engineers (ASABE), EC type approval, and the board of actions of the Nebraska Tractor Test Laboratories (NTTL), were selected and analyzed. Comparison of the test standards: The ISO provides references for fuel and lubricants for tractor tests, and the OECD provides additional measurements for calculating fuel consumption characteristics during the power take-off (PTO) tests. The ISO, EC type approval, and the ASABE provide PTO protective device and the safety requirements. During drawbar power tests, seven transmission ratios are selected for fully automatic transmissions, according to the OECD. In case of hydraulic lift tests, ISO 789-2 and OECD Code 2 advise the use of a static lift force, while SAE J283 advises the use of additional dynamic lift capacity tests for a better representation of in-field operations. The OECD, the ISO, and EC type approval determine the seat index point (SIP), whereas the ASABE determines the seat reference point (SRP) for roll-over protective structure (ROPS) tests. Diversified measurement tolerances were among the braking performance test standards. The European Union (EU) has developed daily limits for vibration exposures with adaptations from ISO 2631-1. Electromagnetic compatibility evaluations are emerging of high-efficiency tractors due to the long-term conformance to electromagnetic emissions and interferences. Comparisons of tractor test standards discussed in this paper are expected to provide useful information for tractor manufacturers and standards development personnel to improve the performance and safety test standards of tractors.

A Novel Test Scheduling Algorithm Considering Variations of Power Consumption in Embedded Cores of SoCs (시스템 온 칩(system-on-a-chip) 내부 코어들의 전력소모 변화를 고려한 새로운 테스트 스케쥴링 알고리듬 설계)

  • Lee, Jae-Min;Lee, Ho-Jin;Park, Jin-Sung
    • Journal of Digital Contents Society
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    • v.9 no.3
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    • pp.471-481
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    • 2008
  • Test scheduling considering power dissipation is an effective technique to reduce the testing time of complex SoCs and to enhance fault coverage under limitation of allowed maximum power dissipation. In this paper, a modeling technique of test resources and a test scheduling algorithm for efficient test procedures are proposed and confirmed. For test resources modeling, two methods are described. One is to use the maximum point and next maximum point of power dissipation in test resources, the other one is to model test resources by partitioning of them. A novel heuristic test scheduling algorithm, using the extended-tree-growing-graph for generation of maximum embedded cores usable simultaneously by using relations between test resources and cores and power-dissipation-changing-graph for power optimization, is presented and compared with conventional algorithms to verify its efficiency.

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Study on Thermal Environmental Test for XKT-1 (KT-1 Export Version) Aircraft (XKT-1(수출형 KT-1) 항공기 열 환경시험에 관한 연구)

  • Kim, Jinseog
    • Journal of Aerospace System Engineering
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    • v.15 no.3
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    • pp.105-113
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    • 2021
  • This paper delineates the applied thermal environmental test profiles using test conditions and procedures based on MIL-STD-810 Method 501 (High Temperature Test Method) and Method 502 (Low Temperature Test Method). The test profiles have been optimized in order to comply with export customer's requirements and product reliability in high and low temperature environment for XKT-1 (KT-1 Export Version) aircraft. Additionally, the tests are suitable for large sized environmental chambers, which is one of the facilities of ADD (Agency for Defense Development) according to ETEMP (Environmental Test and Evaluation Master Plan). The results of these test profiles and test executions satisfy the customer requirements and product reliability. The present paper can be applied to the other export programs with more severe temperature conditions.

Evaluation of surface roughness of heat-polymerized denture base resin according to the polishing step (연마 과정에 따른 열중합 의치상 레진의 표면 거칠기 평가)

  • Hwang, Seong-Sig;Im, Yong-Woon;Kim, Si-Chul;Han, Min-Soo
    • Journal of Technologic Dentistry
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    • v.37 no.4
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    • pp.205-212
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    • 2015
  • Purpose: The objective of this study was to compare the surface roughness according to polishing process in conventional laboratory techniques used for polishing three different acrylic denture base resins. Materials and methods: Specimen preparation and surface polishing procedures were conducted to manufacturer's recommendation with three heat-polymerized denture base resins. Surface roughness and gloss were measured by a contact type tester and a LED gloss checker using thickness 2 mm and diameter 10 mm. There were five specimens for each acrylic resin material and polishing procedures. Mean average surface roughness (Ra) values of each specimen group were analyzed using a one-way ANOVA analysis of variance and Scheffe's post hoc test. Surfaces after surface roughness and gloss testing according to each polishing process were evaluated under a stereoscopic microscope. Results: The highest mean average surface roughness was measured($Ra=2.43{\pm}0.47$) for surfaces finished with a denture tungsten carbide bur in Triplex. The lowest surface roughness values ($Ra=0.11{\pm}0.07$) were determined in Vertex polished with a lathe. In addition, all materials revealed that surface roughness determined highly in HP1 and HP2 than other procedures. All correlation between surface roughness and gloss showed highly with three heat-polymerized resins. Specially, topmost correlation revealed than other material in Triplex. Significant differences in mean average surface roughness were found between polishing process used high speed lathe and low speed hand-piece. Conclusion: Laboratory polishing used to high speed was found to produce the smoothest surface of heat-polymerized denture base acrylic resin. Therefore, we recommended that high polishing process need to get smooth surface.

Optimal Conditions of Single Cell Gel Electrophoresis (Comet) Assay to detect DNA single strand breaks in Mouse Lymphoma L5178Y cells

  • Ryu, Jae-Chun;Kwon, Oh-Seung;Kim, Hyung-Tae
    • Environmental Mutagens and Carcinogens
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    • v.21 no.2
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    • pp.89-94
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    • 2001
  • Recently, single cell gel electrophoresis, also known as comet assay, is widely used for the detection and measurement of DNA strand breaks in vitro and in vivo in many toxicological fields such as radiation exposure, human monitoring and toxicity evaluation. As well defined, comet assay is a sensitive, rapid and visual method for the detection of DNA strand breaks in individual cells. Briefly, a small number of damaged cells suspended in a thin agarose gel on a microscope slide were lysed, unwinded, electrophoresed, and stained with a fluorescent DNA binding dye. The electric current pulled the charged DNA from the nucleus such that relaxed and broken DNA fragments migrated further. The resulting images which were subsequently named for their appearance as comets, were measured to determine the extent of DNA damages. However, some variations could be occurred in procedures, laboratories's conditions and kind of cells used. Hence, to overcome and to harmonize these matters in comet assay, International Workshop on Genotoxicity Test Procedure (IWGTP) was held with several topics including comet assay at Washington D.C. on March, 1999. In spite of some consensus in procedures and conditions in IWGTP, there are some problems still remained to be solved. In this respect, we attempted to set the practical optimal conditions in the experimental procedures such as lysis, unwinding, electrophoresis and neutralization conditions and so on. First of all, we determined optimal lysis and unwinding time by using 150 $\mu$M methyl methanesulfonate (MMS) which is usually used concentration. And then, we determined optimal positive control concentrations of benzo(a)pyrene (BaP) and MMS in the presence and absence of S9 metabolic activation system, respectively.

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Protected versus Unprotected Carotid Artery Stenting : Meta-Analysis of the Current Literature

  • Cho, Young Dae;Kim, Sung-Eun;Lim, Jeong Wook;Choi, Hyuk Jai;Cho, Yong Jun;Jeon, Jin Pyeong
    • Journal of Korean Neurosurgical Society
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    • v.61 no.4
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    • pp.458-466
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    • 2018
  • Objective : To compare peri-operative any symptomatic stroke after carotid angioplasty and stenting (CAS), based on the application or absence of a cerebral protection device. Methods : A systematic literature review using PubMed, Embase, and the Cochrane Central was done across an online data base from January 1995 to October 2016. Procedures which were performed due to carotid dissection or aneurysm, procedures using covered stents or conducted in an emergency, were excluded. The primary endpoint was perioperative any symptomatic stroke within 30 days after the procedure. A fixed effect model was used in cases of heterogeneity less than 50%. Results : In the 25 articles included in this study, the number of stroke events was 326 (2.0%) in protected CAS and 142 (3.4%) in unprotected CAS. The use of cerebral protection device significantly decreased stroke after CAS (odds ratio [OR] 0.633, 95% confidence interval [CI] 0.479-0.837, p=0.001). In the publication bias analysis, Egger's regression test disclosed that the intercept was -0.317 (95% CI -1.015-0.382, p=0.358). Regarding symptomatic patients (four studies, 539 CAS procedures), the number of stroke was six (1.7%) in protected CAS and 11 (5.7%) in unprotected CAS. The protective effect against stroke events by cerebral protection device did not have a statistical significance (OR 0.455, 95% CI 0.151-1.366, p=0.160). Conclusion : The use of protection device significantly decreased stroke after CAS. However, its efficacy was not demonstrated in symptomatic patients. Routine use of protection device during CAS should be critically assessed before mandatory use.

Seizure Control in Patients with Extratemporal Lobe Epilepsy

  • Park, Seung-Soo;Koh, Eun-Jeong;Oh, Young-Min;Lee, Woo-Jong;Eun, Jong-Pil;Choi, Ha-Young
    • Journal of Korean Neurosurgical Society
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    • v.41 no.5
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    • pp.283-290
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    • 2007
  • Objective : This study was designed to analyze seizure outcome and to investigate the prognostic factors for predicting seizure outcome according to the preoperative evaluations, surgical procedures, topectomy sites and histopathological findings in patients with extratemporal lobe epilepsy [ETLE]. Methods : This study comprised 63 patients with ETLE who underwent surgery. Preoperative evaluations included semiologic analysis, chronic video-EEG monitoring, and neuroimaging studies. Surgical procedures consisted of topectomy in 51 patients, corpus callosotomy in 9, functional hemispherectomy in 2, and vagus nerve stimulation [VNS] in 1. Histopathological findings were reviewed. Postoperative seizure outcomes were assessed by Engel's classification at the average follow up period of 66.8 months. Chi-square test was used for statistics. Results : Total postoperative seizure outcomes were class I in 51 [80%] patients, class II in 6 [10%], class III in 6 [10%]. Patients with structural abnormalities on neuroimaging study showed class I in 49 [88%] patients [p<0.05]. Patients with focal and regional ictal EEG onset revealed class I in 47 [90%] patients [p<0.05]. Semiologic findings, surgical procedures, topectomy sites and histopathological findings did not show statistical correlation with seizure outcome [p<0.05]. Conclusion : A good seizure outcome was obtained in patients with ETLE. The factors for favorable seizure outcome are related to the presence of structural abnormalities on neuroimaging study, and focal and regional ictal EEG onset.

Rhamnose-rich and fucose-rich oligo- and polysaccharides (RROP-s and FROPs), agonists and antagonists of cell-membrane receptors as new active principles against skin aging.

  • Robert, L.;Robert, A.M.;Gesztes, J.L.;Luppi, E.
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.352-373
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    • 2003
  • Rhamnose-rich (RROP-s) and fucose-rich (FROP-s) oligo-and polysaccharides were prepared and extensively characterised by physical and chemical procedures [1,2] and compared to L-fucose. Their biological properties were then studied on human skin fibroblast cell cultures, human skin explant cultures and on hairless rat skin, using a variety of cell-biological, biochemical and computerised morphometrical procedures. Among the most important properties we could establish, the following are of particular interest for the tretment and prevention of age-dependent modifications of human skin (loss of skin-tissue, cells and matrix, wrinkle formation and others) : stimulation of cell proliferation (by $^3$[H]-thymidine incorporation and the MTT test), scavenging of reactive oxygen species (ROS) using several different procedures, and protease (MMP-2 and MMP-9) down-regulation. A topical preparation, using RROP-s and FROP-s, and/or L-fucose, was shown to increase cell proliferation, dermal matrix synthesis, efficient scavenging of ROS-s and to increase also the thickness of dermal tissue when applied for 4 weeks on hairless rat skin, accompanied by the densification of collagen bundles as well as by an increase of elastin synthesis. Using fluorescent labeled FROPs, it could be shown that these oligosaccharides react with cell-membrane receptors and especially with the elastin-laminin-receptor and the fucose-mannose receptor, but they penetrate also in the cell nucleus, suggesting the possibility of a direct action on the regulation of gene expression. When applied to the human skin of a team of voluntary women encompassing all age-groups, the efficiency of FROP-containing preparation could be confirmed using indentometry and computerised evaluation of skin micro-relief, as well as evaluation of periorbital wrinkles. It appears therefore that these preparations correspond to all the requirements of active anti-aging principles.

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EFFECT OF TYPE AND CEMENTATION METHOD OF POST-CORE ON MICROLEAKAGE (포스트코어의 종류와 접착방법이 미세누출에 미치는 영향)

  • Yun Myoung-Jae;Lee Sun-Hyung;Yang Jae-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.32 no.2
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    • pp.225-233
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    • 1994
  • The restorations of the severely damaged teeth by post core have been increased with the developement of endodontic procedures. But high failure rates of these procedures being reported, various restorative modifications were induced for successful treatments. Cast post-core and prefabricated post with core buildups are choice of treatment. The main causes of failure of the restorations are the fracture of post and core, root fracture, and recurrent caries due to microleakage. Recently, the acid etching technique and the use of dentin bonding agent at tooth surface to reduce the possible microleakage at the tooth-restoration interfaces were introduced. The object of this study was to measure and compare the microleakage by the types and cementation methods of post-core. For this study, forty extracted human anterior teeth were selected for specimen. After cleansing and routine endodontic procedures, anatomic crowns of each specimen were removed at the level of 2mm above the cementoenamel junction. Canals were preparated for post insertion and specimens were divided into four groups randomly. Post-cores were fabricated according to method for each group. Microleakage was measured by length of dye penetration at the tooth-restoration interfaces with measuring microscope at 50 magnification. Oneway ANOVA and t-test were performed for statistical analysis of resulting data. The following results were obtained from this study. 1. There wert significant statistical differences in degree of microleakage between each group (p<0.01). 2. Cast post-core cemented with ZPC (Group I) showed the most severe microleakage pattern$(1.5547{\pm}0.0872mm)$, and cast post-core cemented with adhesive resin cement after tooth surface treatment with dentin bonding agent (Group II) showed the least microleakage $(0.1497{\pm}0.0872mm)$. 3. Group IV revealed less dye penetrations than group III, but no statistical significance was seen between two groups.

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A Research on Perceptions of the Wedding Ceremony of Unmarried People for the Succession of Korean Traditional Wedding Culture (한국전통혼례문화의 계승을 위한 혼례절차에 대한 미혼남녀의 인식연구)

  • Ju, Young-Ae
    • Journal of Family Resource Management and Policy Review
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    • v.14 no.1
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    • pp.57-71
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    • 2010
  • The purpose of this study was to explore perceptions and awareness of traditional Korean wedding ceremonies. For this purpose, I began a literature review and investigated the consciousness about traditional Korean wedding ceremonies among unmarried people. As a result, I discussed the future of Korean wedding culture. Data were analyzed from the sample of 206 unmarried people collected from April 20 to Jun 13, 2009. The data were analyzed by making use of the SPSS program and included Frequency analysis, ANOVA and the $\chi^2$-test. The summary of these results was as follows. First, unmarried people want a special wedding ceremony. They think the appropriate age of marriage is between their 20s and mid-30s. The traditional wedding ceremony is changing, but they think that the meanings behind them will continue. If they married a foreigner, they would want to have a modem wedding ceremony and each of their traditional wedding ceremonies. Second, they have no educational experience about traditional wedding culture(85.4%). Some people who have educational experience learned about traditional wedding culture from their parents or grandparents. Third, most traditional wedding procedures were influenced by Korean customs. Most men did not know about traditional Korean wedding procedures. But if they get married, they will follow traditional wedding procedures (M=3.35). In the future, we will have to succeed Korean wedding culture, for example, Peau back(幣帛), Ham(函), and traditional wedding ceremony.

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