• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.2
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• pp.449-454
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• 2010

In this paper, flow characteristics of R600a in an adiabatic capillary tube were investigated employing the homogeneous flow model. The model is based on fundamental equations of mass, energy and momentum which are solved simultaneously. Two friction factors(Churchill) and viscosity(McAdams) are comparatively used to investigate the flow characteristics. Thermodynamic and transport properties of R600a are calculated employing EES property code. Flow characteristics analysis of R600a in an adiabatic capillary tube is presented to offer the basic design data for the operating parameters. The operating parameters considered in this study include condensation temperature, evaporation temperature, subcooling degree and inner diameter tube of the adiabatic capillary tube. The main results were summarized as follows: condensation and evaporation temperature, inlet subcooling degree and inner diameter tube of an adiabatic capillary tube using R600a have an effect on length of an adiabatic capillary tube. The length of an adiabatic capillary tube using R600a is expressed to the correlation shown in Eq. (15).

• Journal of Adhesion and Interface
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• v.7 no.4
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• pp.1-9
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• 2006

The single lap joint is the most studied joint in the literature in terms of both theory and practice. It is easy to manufacture and the lap shear strength is a useful value for strength assessment and quality control. Simple design rules exist such as the one present in standard ASTM 1002 or in a recent paper by Adams and Davies. The main factors that have an influence on the lap shear strength are the type of adhesive, i.e. ductile or brittle, the adherend yield strength and the overlap length. The overlap increases the shear strength almost linearly if the adhesive is sufficiently ductile and the adherend does not yield. For substrates that yield, a plateau is reached for a certain value of overlap corresponding to the yielding of the adherend. For intermediate or brittle adhesives, the analysis is more complex and needs further investigation. In order to quantify the influence of the adhesive, the adherend and the overlap on the lap shear strength, the experimental design technique of Taguchi was used. An experimental matrix of 27 tests was designed and each test was repeated three times. The influence of each variable could be assessed as well as the interactions between them using the statistical software Statview. The results show that the most important variable on the lap shear strength is the overlap length followed by the type of adherend.

• Journal of Fisheries and Marine Sciences Education
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• v.21 no.2
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• pp.230-236
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• 2009

Growth status of the Littleneck calm Ruditapes philippinarum (Adams et Reeve) in Komso Bay was investigated by 600 individuals from February 2003 to January 2004. Based on the monthly variation of marginal growth rate of the shellfish, it was suggested that ring formation occurres between January and March once a year and takes approximately 19 months (1.58 old ages) to form a complete ring. The relationship between the shell height(SH) and the total weight(TW) could be represented by the following equation $TW=2.8{\times}\;10^{-3}SH^{2.3648}$. And the relationship between the shell height(SH) and shell length(SL) as well as the shell width(SW) were represented by equations SL=1.0027SH+5.812 and SW=0.5121H+1.2849 respectively. Growth curves for shell height and total weight fitted to the Bertalanffy's equation were expressed as $SH_t=42.83(1-e^{-0.4595(t-0.59)})$ and $TW_t=20.17(1-e^{-0.4595(t-0.59)})^{2.3648.}$

• Journal of Forest and Environmental Science
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• v.30 no.4
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• pp.322-330
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• 2014

This study was conducted during May to September in 2012 to investigate the distribution and diversity of beetles in Mt. Jangsan (634 m) located near Busan, Republic of Korea. The collection of beetles was repeated 11 times in the four areas classified according to altitudes 200 m, 400 m, 600 m, and over 600 m (approximately) on the south and north slopes of Mt. Jangsan. A total of 12 families, 20 species, and 4,343 individual beetles were collected. In the southern slopes, a total of 12 families, 20 species, and 2,264 individuals were collected, whereas a total of 12 families, 20 species, and 2,079 individuals on the northern slopes were captured. The monthly emergence of beetles was the highest in August at 651 individuals followed by 516 individuals in September, 496 individuals in July, 364 individuals in Jun, 237 individuals in May. In the northern slopes, the monthly emergence of beetles was the highest in August as 591 individuals followed by 512 individuals in September, 443 individuals in July, 321 individuals in June, and 212 individuals in May. On the southern slopes, the species diversity index, evenness index, and dominance value were 0.950, 0.730, and 0.181, respectively, while in the northern slopes, the species diversity index, evenness index, and dominance index were 0.946, 0.727, and 0.182, respectively. In the both slopes, the species diversity index and evenness index were the highest in May, while dominance index was the highest in September. This study lays the groundwork for further monitoring of these sites and others through the region for environmental changes using the indicator species.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.5
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• pp.379-384
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• 2014

This article describes the dynamic behaviors of a rubber tired gantry crane(RTGC) under typical load conditions which are used in the design of gantry cranes. In order to investigate the dynamic characteristics of an RTGC, we developed a finite element crane model for its huge structure. The finite element model was validated with the modal test results, e.g., natural frequencies and normal modes. And other components of RTGC were converted into detailed 3D CAD models and finally transformed to rigid body models in a dynamic simulation program ADAMS. The load conditions considered in this paper were a normal operating condition(OP1) and container hanging condition with no external loads. As a result, we could find there was large influence of crane's vibration owing to its structural stiffness and deformation. And the vibration of crane could made the movements of RTGC, which occurs crash or malfunction of crane works.

• Korean Journal of Logic
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• v.8 no.2
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• pp.59-84
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• 2005

Adams' Thesis, or the so-called equation Pr$(A{\rightarrow}C)$ = Pr(C|A) seems to express a correct relationship between the probabilities of conditionals and conditional probabilities. But D. K. Lewis has proved the remarkable fact that probabilities of conditionals are not conditional probabilities. In this paper 1 present a version of Lewis' triviality results and give an explanation why probabilities of conditionals are not conditional probabilities. A conditional probability of C given A has a peculiar properly in that its probability is insulated from not-A facts: the only thing relevant is the proportion of ways in which A is true which are also ways for C to be true. This peculiarity of conditional probability seems to put the great obstacle in the way of attempting to find a proposition such that its probability of being true systematically coincides with conditional probability of something else.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.6 s.237
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• pp.737-746
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• 2005

The present study investigates heat/mass transfer and flow characteristics in a ribbed rotating passage with turning region. The duct has an aspect ratio (W/H) of 0.5 and a hydraulic diameter ($D_h$) of 26.67 mm. Rib turbulators are attached in the cross arrangement on the leading and trailing surfaces of the passage. The ribs have a rectangular cross section of $2\;mm\;(e){\times}\;mm\;(w)$ and an attack angle of $70^{\circ}$. The pitch-to-rib height ratio (p/e) is 7.5, and the rib height-to-hydraulic diameter ratio ($e/D_h$) is 0.075. The rotation number ranges from 0.0 to 0.20 while the Reynolds number is constant at 10,000. To verify the heat/mass transfer augmentation, internal flow structures are calculated for the same conditions using a commercial code FLUENT 6.1. The heat transfer data of the smooth duct for various Ro numbers agree well with not only the McAdams correlation but also the previous studies. The cross-rib turbulators significantly enhance heat/mass transfer in the passage by disturbing the main flow near the surfaces and generating one asymmetric cell of secondary flow skewing along the ribs. Because the secondary flow is induced in the first-pass and turning region, heat/mass transfer discrepancy is observed in the second-pass even for the stationary case. When the passage rotates, heat/mass transfer and flow phenomena change. Especially, the effect of rotation is more dominant than the effect of the ribs at the higher rotation number in the upstream of the second-pass.

• Clinical and Experimental Reproductive Medicine
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• v.44 no.1
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• pp.40-46
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• 2017

Objective: To describe in vitro development of human embryos derived from an individual with a homozygous pathogenic variant in NLRP7 (19q13.42) and recurrent hydatidiform mole (HM), an autosomal recessive condition thought to occur secondary to an oocyte defect. Methods: A patient with five consecutive HM pregnancies was genomically evaluated via next generation sequencing followed by controlled ovarian hyperstimulation, in vitro fertilization (IVF) with intracytoplasmic sperm injection, embryo culture, and preimplantation genetic screening. Findings in NLRP7 were recorded and embryo culture and biopsy data were tabulated as a function of parental origin for any identified ploidy error. Results: The patient was found to have a pathogenic variant in NLRP7 (c.2810+2T>G) in a homozygous state. Fifteen oocytes were retrieved and 10 embryos were available after fertilization via intracytoplasmic sperm injection. Developmental arrest was noted for all 10 embryos after 144 hours in culture, thus no transfer was possible. These non-viable embryos were evaluated by karyomapping and all were diploid biparental; two were euploid and eight had various aneuploidies all of maternal origin. Conclusion: This is the first report of early human embryo development from a patient with any NLRP7 mutation. The pathogenic variant identified here resulted in global developmental arrest at or before blastocyst stage. Standard IVF should therefore be discouraged for such patients, who instead need to consider oocyte (or embryo) donation with IVF as preferred clinical methods to treat infertility.

• The Korean Journal of Malacology
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• v.7 no.1
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• pp.1-11
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• 1991

Authors describe here five new species and three new subspecies of Korean Iand snail fauna. They are collected from the southern part of Korea including Ullungdo and Chejudo. The generic names of these new species and subspecies were discribed in the [ Il-lustrated Encyclopedia of fauna & flora of Korea V ol.32 Mollusca(I)]. The newly recorded species and subspecies are as follows:Genus Diplommatina Benson, 1849 Subgenus Sinica Mollendorff, 1885 Diplommatina(Sinica) paxillus changensis n. subsp. Diplommatina(Sinica) chejuensis n. sp.Genus Arinia H. & A. Adams, 1856 Arinia chejuensis n. sp.Authors describe here five new species and three new subspecies of Korean Iand snail fauna. They are collected from the southern part of Korea including Ullungdo and Chejudo. The generic names of these new species and subspecies were discribed in the [ Il-lustrated Encyclopedia of fauna & flora of Korea V ol.32 Mollusca(I)]. The newly recorded species and subspecies are as follows:Genus Diplommatina Benson, 1849 Subgenus Sinica Mollendorff, 1885 Diplommatina(Sinica) paxillus changensis n. subsp. Diplommatina(Sinica) chejuensis n. sp.Genus Cavernacmella Habe, 1942 cavernacmella coreana n. sp.Authors describe here five new species and three new subspecies of Korean Iand snail fauna. They are collected from the southern part of Korea including Ullungdo and Chejudo. The generic names of these new species and subspecies were discribed in the [ Il-lustrated Encyclopedia of fauna & flora of Korea V ol.32 Mollusca(I)]. The newly recorded species and subspecies are as follows:Genus Diplommatina Benson, 1849 Subgenus Sinica Mollendorff, 1885 Diplommatina(Sinica) paxillus changensis n. subsp. Diplommatina(Sinica) chejuensis n. sp.Genus Mirus Albers, 1850 Mirus junensis n. sp.Genus Paganizaptyx Kuroda, 1945 Paganizaptyx miyanagai ullungdoensis. subsp.Authors describe here five new species and three new subspecies of Korean Iand snail fauna. They are collected from the southern part of Korea including Ullungdo and Chejudo. The generic names of these new species and subspecies were discribed in the [ Il-lustrated Encyclopedia of fauna & flora of Korea V ol.32 Mollusca(I)]. The newly recorded species and subspecies are as follows:Genus Diplommatina Benson, 1849 Subgenus Sinica Mollendorff, 1885 Diplommatina(Sinica) paxillus changensis n. subsp. Diplommatina(Sinica) chejuensis n. sp.Genus Ratinella Shuttleworth, 1877 Retinella radiatula coreana n. subsp.Genus Sitalina Thiele, 1931 Sitalina chejuensis n. sp.

• Smart Structures and Systems
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• v.25 no.5
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• pp.559-567
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• 2020

Vibration at the tip of various flexible manipulators may affect their operation accuracy and work efficiency. To suppress such vibrations, the feasibility of using MFC actuators and sensors is investigated in this paper. Considering the convergence of the famous filtered-x least mean square (FXLMS) algorithm could not be guaranteed while it is employed for vibration suppression of plants with varying secondary path, this paper proposes a new multiple model switching adaptive control algorithm to implement the real time active vibration suppression tests with a new multiple switching strategy. The new switching strategy is based on a cost function with reconstructed error signal and disturbance signal instead of the error signal from the error sensor. And from a robustness perspective, a new variable step-size sign algorithm (VSSA) based FXLMS algorithm is proposed to improve the convergence rate. A cantilever beam with varying tip mass is employed as flexible manipulator model. MFC layers are attached on both sides of it as sensors and actuators. A co-simulation platform was built using ADAMS and MATLAB to test the feasibility of the proposed algorithms. And an experimental platform was constructed to verify the effectiveness of MFC actuators and sensors and the real-time vibration control performance. Simulation and experiment results show that the proposed FXLMS algorithm based multiple model adaptive control approach has good convergence performance under varying load conditions for the flexible cantilever beam, and the proposed FX-VSSA-LMS algorithm based multiple model adaptive control algorithm has the best vibration suppression performance.