• The Mathematical Education
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• v.47 no.4
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• pp.421-436
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• 2008

Mathematics assessment doesn't mean examining in the traditional sense of written examination. Mathematics assessment has to give the various information of grade and development of students as well as teaching of teachers. To achieve this purpose of assessment, we have to search the methods of assessment. This paper is aimed to develop the open-ended problems that are the alternative to traditional test, apply them to classroom and analyze the result of assessment. 4-types open-ended problems are developed by criteria of development. It is open process problem, open result problem, problem posing problem, open decision problem. 6 grade elementary students who are picked in 2 schools participated in assessment using open-ended problems. Scoring depends on the fluency, flexibility, originality The result are as follows; The rate of fluency is 2.14, The rate of flexibility is 1.30, and The rate of originality is 0.11 Furthermore, the rate of originality is very low. Problem posing problem is the highest in the flexibility and open result problem is the highest in the flexibility. Between general mathematical problem solving ability and fluency, flexibility have the positive correlation. And Pearson correlational coefficient of between general mathematical problem solving ability and fluency is 0.437 and that of between general mathematical problem solving ability and flexibility is 0.573. So I conclude that open ended problems are useful and effective in mathematics assessment.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.8
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• pp.669-672
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• 2004

This paper considers the implementation and experiments of an open-loop Cylindrical Vibratory Gyroscope(CGV). An open-loop CGV composed of thin cylindrical vibrating element, electromagnetic drive and pick-off element with open-loop control was designed and fabricated. The experimental performance tests of the open-loop CGV were done using a temperature chambered rate table. Also, the limitations of open-loop CGV were analyzed and the solution for the limitations was proposed.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.46 no.6
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• pp.373-378
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• 2020

The purpose of this review is to assess the surgical outcomes of two different treatment modalities, endoscopic and open resection, for the management of sinonasal malignancies by comparing the effectiveness of these two methods. A wide search was carried out considering various electronic databases for English language articles from 2013 to 2018 using keywords such as sinonasal malignancies, endoscopic surgery, open resection for sinonasal malignancies, and endoscopic versus open surgery. One thousand articles were identified from the literature for screening. After a thorough systematic assessment and based on the selection criteria, 10 articles with 4,642 patients were included in this quantitative analysis. With a total of 4,642 patients, 1,730 patients were operated on using endoscopic resection and 2,912 patients were operated on using open resection. The endoscopic approach was found to have a shorter hospital stay compared to open surgical resection (P<0.05). The rate of positive margins and the recurrence rate for open surgical resection were both smaller compared to those for endoscopic resection (P>0.05), and the endoscopic approach had smaller complication rates and a higher survival rate compared to open resection (P>0.05). Though endoscopic resection and open surgical resection have comparable postoperative benefits, preoperative evaluation of cases presenting with sinonasal malignancies is necessary for determining the right treatment method to obtain the best possible results postoperatively.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.13 no.3
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• pp.9-15
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• 2017

In this study, set values of PICV(Pressure Independent Control Valve) were simulated according to the pressure distribution and velocity. The higher the set value and the open rate, as the lower the pressure in the neck. On the contrary, the lower the set value and open rate, as the higher the pressure in the neck. When the set value was small, the pressure was distributed sufficiently and confirmed that the pressure was generated by the VOF, confirming that it could generate a vapor pressure. When the set value 100 %, the lower corn open rate of the differential pressure was 46 % to 29 %, set value 100 % was 29 % to 19 %, and set value 6 % was 12 % to 6 % for the lower corn open rate percentile, it was limited to within 50 %. Thus, the results of this study on the correlation between open rate and differential pressure of the set value of the PICV will be beneficial to improve performance of flow control valves and contribute to their efficient operation used for a hydronic system.

• East Asian Economic Review
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• v.18 no.3
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• pp.301-335
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• 2014

In this paper, we consider a small open economy under the New Keynesian model with unemployment of Gal$\acute{i}$ (2011a, b) to discuss the design of the monetary policy. Our findings can be summarized in three parts. First, even with the existence of unemployment, the optimal policy is to minimize variance of domestic price inflation, wage inflation, and the output gap when both domestic price and wage are sticky. Second, stabilizing unemployment rate is important in reducing the welfare loss incurred by both technology and labor supply shocks. Therefore, introducing the unemployment rate as an another argument into the Taylor-rule type interest rate rule will be welfare-enhancing. Lastly, controlling CPI inflation is the best option when the policy is not allowed to respond to unemployment rate. Once the unemployment rate is controlled, however, stabilizing power of CPI inflation-based Taylor rule is diminished.

• Korean Journal of Microbiology
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• v.28 no.1
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• pp.19-26
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• 1990

To examine the effects of sequence variations near the transcriptional start site on the rate of formation of the open complexes at bacteriophage $\lambda P_{R}$ promoter, two mutant promoters were created by site-specific mutagenesis using synthetic oligonucleotides. Mutant I coatains changes at positions -3 and -4 from TT to CC, thus having a 6-bp long G/C stretch between -10 region and transciptional start site (+1). Mutant II has changes at positions -5 and -6 from GG to AA, thereby having a 9-bp long A/T stretch between positions -11 and -3. Selective filter binding assays were performed to measure the rate of formation of the open complexes between the wild-type or two mutant $P_{R}$ promoters on 664 bp fragments and E. coli RNA polymerase at two temperatures. At 37.deg.C, the wild-type and two mutants showed similar rates for the formation of open complex. The second order rate constant $k_{a}$ and $\tau _{int}$, as determined from the .tau.-plot analysis, were $(6.0\pm0.4)\times10^{6}M^{-1}sec^{-1}$ and $11\pm5$sec, respectively. At 18.deg.C, however, the wild-type and two mutant promoters showed differences in the kinetic parameters. k for the wild-type promoter was (2.2$\pm$0.1)\times 10^{6}M^{-1}sec^{-1}$ and $\tau _{int}$ was 76$\pm$sec. Mutant I and II exhibited differences mainly in the rate of isomerization ($\tau_{int,I}=91\pm$10 sec, int,II=34$\pm$ sec), whereas the second order rate constant $k_{a}$ was similar to the wild type value. This result implies that at $18^{\circ}C$, the isomerization rate is determined by both protein conformational change and DNA melting, which are separable kinetically according to the 3-step mechanism of Roe et al.(1984,1985), and that the base changes affected mainly the rate of DNA melting as predicted.lting as predicted.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.2A
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• pp.154-167
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• 2006

Today's IEEE 802.11 WLANs(Wireless LANs) provide multiple transmission rates so that different rates can be exploited in an adaptive manner depending on the underlying channel condition in order to maximize the system performance. Many rate adaptation schemes have been proposed so far while most(if not all) of the commercial devices implement a simple open-loop rate adaptation scheme(i.e., without feedback from the receiver), called ARF(Automatic Rate Fallback) due to its simplicity. A key problem with such open-loop rate adaptation schemes is that they do not consider the collision effect, and hence, malfunction severely when many transmission failures are due to collisions. In this paper, we propose a novel rate-adaptation scheme, called CARA(Collision-Aware Rate Adaptation). The key idea of CARA is that the transmitter station combines adaptively the Request-to-Send/Clear-to-Send(RTS/CTS) exchange with the Clear Channel Assessment(CCA) functionality to differentiate frame collisions from frame transmission failures cause by channel errors. Therefore, compared with other open-loop rate adaptation schemes, CATA is more likely to make the correct rate adaptation decisions. Through extensive simulation runs, we evaluate our proposed scheme to show that our scheme yields significantly higher throughput performance than the existing schemes in both static and time-varying fading channel environments.

• Korean Journal of Child Studies
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• v.21 no.3
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• pp.53-68
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• 2000

This study investigated differences between the ability of children and young adults to describe their experience. Forty 5-year-olds and 40 16-year-olds viewed 12 pictures(Azmitia, 1987) and responded to open-ended, closed and misleading questions. Responses were categorized by the SPSS WIN program into rate of correctness, incorrectness, unresponsiveness and "don't know". Data were analyzed by t-test. On open-ended questions, the rate of incorrectness by young adults was higher than that of children. On closed questions, children had a higher rate of incorrectness than young adults. On misleading questions, children showed a lower performance in the rate of correctness and "don't know" and the rate of incorrectness by children was higher than that of young adults.

• East Asian Economic Review
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• v.27 no.2
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• pp.115-143
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• 2023

In this paper, we address how the monetary authority should react to financial market status and exchange rate movements in a small open economy New Keynesian model with financial frictions due to asymmetric information between savers and borrowers. We show that the small economy with financial frictions is more susceptible to the exogenous shocks under the fixed exchange rate regime than under the flexible exchange regime. The small economy experiences a more prolonged and deeper economic recession under the fixed exchange rate regime than under the flexible exchange rate regime. The monetary policy taking into account external finance premium is better than the interest rate rule without considering the financial market status.

• International Journal of Reliability and Applications
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• v.4 no.2
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• pp.51-56
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• 2003

A k-out-of-n system with n identical and independent components is considered in which the components takes two types of function: 0 (open-circuit) or 1 (closed) on command (e.g. electromagnetic relays and solid state switches). Components are subject to two types of failure on command: failure to close or failure to open. In our k-out-of-n system, failure of (n-k)＋1 or more components to close causes to the close failure of the system, or failure of k or more components to open causes the open failure of the system. The long-run average cost rate is obtained. We find the optimal k minimizing the long run average cost rate for given n. A numerical example is presented.