• International Journal of Air-Conditioning and Refrigeration
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• v.11 no.4
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• pp.209-217
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• 2003

The term “energy saving is economical” is appropriate for the national view point and for design and assessment of one system, but not appropriate when choosing the system by comparing alternative systems in the early design step. Sometimes, non-energy saving system is more economical than energy saving system because of the price of electricity, gas or oil, which are used for operating the air conditioning system. Therefore, when designing a system, we should consider the efficient alternatives through economic assessment of energy saving method. However, research on non-operating number control of the system is not sufficient because it is more common to use operating number control of the system for most economic assessment of air conditioning systems. For this reason, this research can provide the economic operating number control method as basic design data. The data obtained through analysis of life cycle cost based on amount of yearly energy use, are produced by system simulation of HASP/ACLD/8501 and HASP/ACSS/8502 for six alternative heating$.$cooling systems based on seasonal air conditioning system, which is widely used for medium and large size office buildings in Busan.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.259-262
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• 2009

The influence of pre-strain in low-cycle fatigue behavior of Fe-18Mn-0.05Al-0.6C TWIP steel was studied by conducting axial strain-controlled tests. As-received plates were deformed by rolling with reduction ratios of 10 and 30%, respectively. A triangular waveform with a constant frequency of 1 Hz was employed for low cycle fatigue test at the strain amplitudes in the range of ${\pm}0.4{\sim}{\pm}0.6$ pct. The results showed that low-cycle fatigue life was strongly dependent on the amount of pre-strain as well as the strain amplitude. Increasing the amount of prestrain, the number of reversals to failure was significantly decreased at high strain amplitudes, but the effect was negilgible at low strain amplitudes. A new model for predicting fatigue life of pre-strained body has been devised adding a correction term of ${\Delta}E_{pre-strain}$ to the energy-based fatigue damage parameter.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.285-290
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• 2004

Low cycle fatigue tests are performed on the Inconel 617 that be used for a hot gas casing. The relation between strain energy density and numbers of cycles to failure is examined in order to predict the low cycle fatigue life of Inconel 617. The life predicted by the strain energy method is found to coincide with experimental data and results obtained from the Coffin-Manson method. Also the cyclic behavior of Inconel 617 is characterized by cyclic hardening with increasing number of cycle at room temperature.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.59
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• pp.1-10
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• 2000

The traveling salesman problem is a representative NP-Complete problem. It needs lots of time to get a solution as the number of city increase. So, we need an efficient heuristic algorithm that gets good solution in a short time. Almost edges that participate in optimal path have somewhat low value cost. This paper discusses the property of nearest neighbor and 3-opt. This paper uses nearest neighbor's property to select candidate edge. Candidate edge is a set of edge that has high probability to improve cycle path. We insert edge that is one of candidate edge into intial cycle path. As two cities are connected. It does not satisfy hamiltonian cycle's rule that every city must be visited and departed only one time. This paper uses 3-opt's method to sustain hamiltonian cycle while inserting edge into cycle path. This paper presents a highly efficient heuristic algorithm verified by numerous experiments.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.6
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• pp.100-108
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• 1993

In this paper, noticing the point of human's ability which appropriately cope with vague conditions, we design fuzzy traffic signal light controller similar to human's distinction ability and decide the optimum cycle most suited to any traffic junction using fuzzy identification algorithm. In this study, for the control output decision process we design fuzzy controller better than electronic vehicle actuated controller in performance. We propose the cycle decision method which is not limited by the variance of traffic junction vehicle number through overcoming the limit of Webster's method which is adopted by the fixed cycle controller. Simulated experimental results show that fuzzy controller and fuzzy identification algorithm are better than the existing electronic vehicle actuated controller and fixed cycle controller in delay time per vehicle.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.612-615
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• 2005

Low cycle fatigue tests are performed on the Incollel 617 that be used fur a hot gas casing. The relation between strain energy density and numbers of cycles to failure is examined in order to predict the low cycle fatigue life of Inconel 617. The life predicted by the strain energy method is found to coincide with experimental data and results obtained from the Coffin-Mansun method. Also the cyclic behavior of Inconel 617 is characterized by cyclic hardening with increasing number of cycle at room temperature.

• Molecules and Cells
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• v.44 no.10
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• pp.699-705
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• 2021

The centrosome is a subcellular organelle from which a cilium assembles. Since centrosomes function as spindle poles during mitosis, they have to be present as a pair in a cell. How the correct number of centrosomes is maintained in a cell has been a major issue in the fields of cell cycle and cancer biology. Centrioles, the core of centrosomes, assemble and segregate in close connection to the cell cycle. Abnormalities in centriole numbers are attributed to decoupling from cell cycle regulation. Interestingly, supernumerary centrioles are commonly observed in cancer cells. In this review, we discuss how supernumerary centrioles are generated in diverse cellular conditions. We also discuss how the cells cope with supernumerary centrioles during the cell cycle.

• Journal of Embryo Transfer
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• v.28 no.4
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• pp.307-314
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• 2013

Embryos formed in vivo were collected from 171 donors housed in Chung Cheong Buk-Do Institute of Livestock and Veterinary Research of the Chungbuk community during the years 2009~2012. We evaluated annual embryo collection, effect of follicle stimulating hormone (FSH), controlled internal drug release (CIDR) and prostaglandin (PG) administration to the donor for superovulation and controlling the estrus cycle, seasonal effects of embryo collection and compared the number of embryos recovered as per the collection days and pregnancy rate. In all, 1,243 embryos were collected from 118 donors with an average of $7.31{\pm}5.35$ embryos per donor, out of which 69.4% were transferable. Dosages of FSH required for inducing superovulation in various donors were compared. Average number of embryos collected from donors administered with 30 AU of FSH ($7.13{\pm}5.74$ per donor) was not significantly different from that of donors who were given an injection of 24 AU of FSH ($7.53{\pm}4.91$ per donor). However, the percentage of transferable embryos in the 30AU FSH-administered group (63.2 %, 449 of 711) was higher than that in the 24AU FSH-administered group (77.8%, 414 of 532). In the group of donors under a natural estrus cycle, the FSH dose administered did not influence the number of transferable embryos produced ($7.49{\pm}6.25$ per donor for 30 AU of FSH vs $7.49{\pm}4.92$ per donor for 24 AU of FSH). However, in donors administered with CIDR and PG for controlling the estrus cycle, the FSH dose affected the average number of transferable embryos collected ($4.25{\pm}2.87$ per donor for 30 AU of FSH vs $8.50{\pm}6.36$ per donor for 24 AU of FSH). We collected embryos from donors 6, 7 or 8 days after artificial insemination (AI). Results showed that the percentage of transferable embryos among those collected 8 days after AI was significantly higher than that among embryos collected 6 or 7 days after AI. Seasonal variations did not affect number of recovered embryos and pregnancy rates in natural estrus cycle and CIDR treatment groups (48.28% and 42.55%) but higher than pregnancy rate of frozen embryos (19.63%). These results indicated that administration of FSH beyond a threshold dose (at least 24 AU) has no beneficial effect on the production embryos and that collection of embryos 7~8 days after AI is optimal for embryo recovery. CIDR treatment induced superovulation in short term and had no influence on the natural estrus cycle. Finally, although good-quality embryos were transferred, freezing significantly reduced the pregnancy rates after transfer.

• Bulletin of the Korean Mathematical Society
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• v.52 no.2
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• pp.467-481
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• 2015

Choi and Park introduced an invariant of a finite simple graph, called signed a-number, arising from computing certain topological invariants of some specific kinds of real toric manifolds. They also found the signed a-numbers of path graphs, cycle graphs, complete graphs, and star graphs. We introduce a signed a-polynomial which is a generalization of the signed a-number and gives a-, b-, and c-numbers. The signed a-polynomial of a graph G is related to the $Poincar\acute{e}$ polynomial $P_{M(G)}(z)$, which is the generating function for the Betti numbers of the real toric manifold M(G). We give the generating functions for the signed a-polynomials of not only path graphs, cycle graphs, complete graphs, and star graphs, but also complete bipartite graphs and complete multipartite graphs. As a consequence, we find the Euler characteristic number and the Betti numbers of the real toric manifold M(G) for complete multipartite graphs G.

• Journal of Veterinary Clinics
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• v.5 no.2
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• pp.83-86
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• 1988

Morphometric observation on the ovarian follicles of ICR strain-female mice has been conducted to investigate the effect of induced inflammation on the follicular populations. Inflammation was induced by administering 25${\mu}\ell$ of turpentine oil intraperitoneally 2 times at the interval of 3 days. Mice showing 5-day estrous cycle about 20 days after induction of inflammation are placed in experimental group. Normal follicles of 100～399$\mu\textrm{m}$ in diameter increased at estrus but those of over 400$\mu\textrm{m}$ decreased. super-ovulation increased the number of normal follicles of over 400$\mu\textrm{m}$. The number of normal follicles of over 400$\mu\textrm{m}$ 48 hours after superovulation was not significantly different between experimental and control groups. Present results indicated that the number of preovulatory follicles 48 hours after PMSG injection did not decrease in the mice which showed regular estrous cycle even after the induction of inflammation.