• Journal of Korean Society of Steel Construction
• /
• v.29 no.4
• /
• pp.303-310
• /
• 2017

The welded unreinforced flange-welded web(WUF-W) connection is an all-welded moment connection, which is qualified for special moment frame(SMF) connections. However, previous studies reported that some WUF-W connections did not meet the drift requirement specified for SMF connections and such unexpected connection performance was resulted from weld access hole geometry. The objective of this study is to determine the permissible ranges of major access hole parameters such as access hole slope and the length of flat portion that lead to the satisfactory performance of WUF-W connections using Nonlinear finite element analyses are conducted. This study also proposes simple empirical equations to check the validity of access hole parameters to be selected in design process.

• Journal of the Ergonomics Society of Korea
• /
• v.35 no.1
• /
• pp.39-52
• /
• 2016

Objective: This paper investigates gait changes according to different heel heights and speeds, and the interaction between the effects of the heel height and the speed during walking on stride parameters and joint angles. Furthermore, the relationship among heel height, speed and gait variables is investigated using linear regression. Background: Gait changes by heel height or speed have been studied respectively, but has not been reported whether there is an interaction effect between heel height and speed. It would be necessary to understand how gait changes when a person wears heels in different heights at various speeds, for example, high-heeled walking at fast speed, since it may cause unusual gait patterns and musculoskeletal disorders. Method: Ten females were asked to walk at five fixed cadences (94, 106, 118, 130 and 142 steps/min.) wearing three shoes with different heel heights (1, 5.4 and 9.8cm). Nineteen gait variables were analyzed for stride parameters and joint angles using two-way repeated measure analysis of variance and regression analysis. Results: Both heel height and speed affect movement of ankle, knee, spine and elbow joint, as well as stride length and Double/Single support time ratio. However, there is no significant interaction effect between heel height and speed. The regression result shows linear relationships of gait variables with heel height and speed. Conclusion: Heel height and speed independently affect stride parameters and joint angles without a significant interaction, so the gait variables are linearly amplified or diminished by the two factors. Application: Walking in high heels at fast speed should be careful for musculoskeletal disorders, since the amplified movement of knee and spine joint can lead to increased moment. Also, the result might give insight for animators or engineers to generate walking motion with high heels at various speeds.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.1
• /
• pp.47-51
• /
• 2013

Background: Postoperative complications after esophagectomy can lead to considerable patient discomfort and prolonged length of hospital stay. Lack of physical activity can be one of the independent risk factors for postoperative complications because physical activity is closely related to physical function. The objective of this study was to determine whether physical activity among esophageal cancer patients decreases their risk of postoperative complications after esophagectomy. Materials and Methods: We investigated 51 consecutive patients with newly diagnosed resectable esophageal cancer who were scheduled to receive esophagectomy between January 2009 and November 2011. Demographic, clinicopathologic, and treatment information were recorded and physical function was measured. The last 7-days short version of the International Physical Activity Questionnaire was used to assess physical activity before the operation. Stepwise multiple logistic regression analysis was used to determine whether preoperative physical activity is related to the risk of postoperative complications. Results: Male gender [OR 18.6, (95%CIs: 1.2-284.4); P=0.035], 3-field lymph node dissection (OR 9.6, [95%CIs: 1.4-66.6]; P=0.022), low-level physical activity (OR 28.3, [95%CIs: 3.5-227.7]; P=0.002), and preoperative comorbidities [OR 5.9, (95%CIs: 1.1-31.5); P=0.037] were found to be independently associated with postoperative complications. Conclusions: The present study shows that low-level physical activity, preoperative comorbidities, and 3-field lymph node dissection are independent and significant risk factors for postoperative complications after esophagectomy. Although further study is required, maintaining high-level physical activity preoperatively may decrease the risk of postoperative complications.

• Journal of Arbitration Studies
• /
• v.24 no.1
• /
• pp.45-58
• /
• 2014

It is a well recognised rule in international law that the property of aliens cannot be taken. The question of whether indirect expropriation and government regulatory measures require compensation is an important issue in international investment law. Bilateral investment treaties and other investment agreements contain brief and general indirect expropriation provisions. These focus on the effect of government action and do not address the distinction between compensable and non-compensable regulatory actions. It is generally accepted that a state is not responsible for loss of property or for other economic disadvantages resulting from bona fide general taxation accepted as within the police power of states, provided it is not discriminatory. Yukos Oil Company is a Russian oil and gas company engaged in exploration, refining, and marketing activities. It is one of the largest oil and gas companies in the world. Yukos Oil Company has its production operations in Russia and markets its products in Europe. An international tribunal ordered the Russian government to compensate a group of Spanish investors for the losses they suffered when Russia seized the Yukos Oil Company on July 26, 2012. This has been the subject of several judicial proceedings and academic publications. This paper explores which circumstances do not lead to taxation amounting to expropriation. The author suggests that under the following circumstances, taxation would not amount to expropriation. First, taxation should be non-discriminatory. Also a lawful exercise of the taxation powers of governments would not amount to expropriation.

• The KIPS Transactions:PartC
• /
• v.12C no.7 s.103
• /
• pp.1039-1046
• /
• 2005

TCP SACK is the unique mechanism to reflect the situation of sink's sequence space, some TCP variants and proposals can perform in conjunction with SACK mechanism for achieving optimal performance. By definition of RFC 2018, however, each contiguous block of data queued at the data receiver is defined in the SACK option by two 32-bit unsigned integers in network byte order. Since TCP Options field has a 40-byte maximum length, when error bursts now, we note that the available option space may not be sufficient to report all blocks present in the receiver's queue and lead to unnecessarily force the TCP sender to retransmit Packets that have actually been received by TCP sink. For overcoming this restriction, in this thesis, a new solution named 'one-byte offset based SACK mechanism' is designed to further improve the performance or TCP SACK and prevent those unwanted retransmissions. The results or both theory analysis and simulation also show that his proposed scheme operates simply and more effectively than the other existing schemes by means of the least bytes and most robust mechanism to the high packet error rates often seen in networks environment.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.51 no.6
• /
• pp.290-297
• /
• 2014

The synchronization of OFDM receiver is consisted of symbol timing offset(STO) estimation in time domain and carrier frequency offset(CFO) estimation in frequency domain. This paper proposes new algorithm for correcting the integer CFO after we have done correcting the STO and partial CFO. ICFO must be corrected, since the ICFO lead to degrade bit error rate(BER) of demodulation performance. The PN sequence has information which is subcarrier order since the modified PN sequence, length is same subcarrier, is used in this paper and is modulated each subcarrier by each chip. Thus the receiver track phase of PN sequence after FFTin order to find the subcarrier frequency offset. The proposed algorithm is faster and more simple than convenient methode as measuring carrier energy.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.32 no.6A
• /
• pp.337-345
• /
• 2012

A model test is performed to investigate the dynamic behavior of truss type lift gate which is being constructed by the four major rivers project. The gate dimensioned 40 m in width, 9m in height is scaled with the ratio of 1:25 and is made of acryl panel and supplemented weight by lead in the concrete test flume dimensioned 1.2 m in width, 0.5 m in height and 30m in length. Firstly natural frequencies of the model gate are measured and compared with the numerical results for the calibration. The amplitudes of the vibration are measured under the different gate opening, upstream water level conditions. Also models with bottom angle $20^{\circ}$, $35^{\circ}$ and $50^{\circ}$ are tested and compared to find out a proper shape of bottom structure which minimizes the gate vibration. These test results presents a basic data for the guide manuals of gate management and a design method to reduce the gate vibration of truss type lift gate.

• The Mathematical Education
• /
• v.59 no.3
• /
• pp.217-235
• /
• 2020

This study examined Korean fourth-grade students' performance by gender on the Trends in International Mathematics and Science Study(TIMSS) 2011 and 2015 mathematics assessment. We first identified items which had significantly higher mean scores by gender to decide which gender did better on a certain domain(domain-level analysis). Then, we examined the content of items(item-level analysis) to understand which items lead to gender differences in mathematics achievement. Our findings showed that about 80% of the items on both assessments did not show statistically significant differences between males and females. However, there were meaningful gender differences in the other 20% items. On both assessments, females had more items with significantly higher mean scores than males on the Shapes domain, and males had more those items on the Numbers and Measurement domains and all cognitive domains(Knowing, Applying, and Reasoning). In particular, females outperformed males on items related to identifying two- and three-dimensional shapes and drawing lines and angles and identifying them. Conversely, males had higher performance than females on items related to the pre-algebraic thinking, fractions and decimals, estimation of number differences, unit of length, and measuring time, height, and volume. The effect sizes for each item ranged from .12 to .33 and the mean effect size of all items across both assessments was .20, which indicated significant gender differences but small.

• Steel and Composite Structures
• /
• v.20 no.5
• /
• pp.1067-1085
• /
• 2016

Recent research on steel moment-resisting connection between steel beams and concrete filled steel tubes has shown that there are considerable advantages to be obtained by anchoring the connection to the concrete infill within the tube using anchors in blind bolts. In the research reported here, extensive experimental tests and numerical analyses have been performed to study the anchorage behaviour of cogged deformed reinforcing bars within concrete filled circular steel tubes. This data in essential knowledge for the design of the steel connections that use anchored blind bolts, both for strength and stiffness. A series of pull-out tests were conducted using steel tubes with different diameter to thickness ratios under monotonic and cyclic loading. Both hoop strains and longitudinal strains in the tubes were measured together with applied load and slip. Various lead-in lengths before the bend and length of tailed extension after the bend were examined. These dimensions were limited by the dimensions of the steel tube and did not meet the requirements for "standard" cogs as specified in concrete standards such as AS 3600 and ACI 318. Nevertheless, all of the tested specimens failed by bar fracture outside the steel tubes. A comprehensive 3D Finite Element model was developed to simulate the pull-out tests. The FE model took into account material nonlinearities, deformations in reinforcing bars and interactions between different surfaces. The FE results were found to be in good agreement with experimental results. This model was then used to conduct parametric studies to investigate the influence of the confinement provided by the steel tube on the infilled concrete.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.17
• /
• pp.7589-7594
• /
• 2015

Background: MicroRNAs (miRNAs) are small non-coding RNA molecules, implicated in several activities like initiation, progression and prognosis of various cancers. Single nucleotide polymorphisms (SNPs) in miRNA genes can lead to alteration in mRNA expression, resulting in diverse functional consequences. The aim of our study was to investigate the association of miR-149C>T and miR-196a2C>T SNPs with susceptibility to development of oral squamous cell carcinoma (OSCC) in South Indian subjects. Materials and Methods: 100 OSCC patients and 102 healthy controls from the general population were recruited for the study. Genetic analysis was performed by polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) as per a standard protocol. Results: The genotype frequencies in miR-196a2 polymorphism, of TT, CT and CC in the OSCC patients were 69%,10% and 22% respectively while for control group it was 80%, 15% and 5% respectively. The CC genotype of miR196a2 polymorphism was significantly associated with oral squamous cell carcinoma. The genotype frequencies in miR-149 polymorphisms of CC, CT and TT in the oral squamous cell carcinoma (OSCC) patients were 72%, 22% and 6% respectively and for control group 88%, 12% and 0% respectively. CT and TT genotypes of miR149 polymorphism were found to be significantly associated with OSCC (p = 0.05 and 0.07). Conclusions: Our study suggests that miR-196a2C>T and miR-149C>T polymorphisms may play crucial roles in the development of OSCC in South Indian subjects.