Impact Severity is important parameter to design concrete barrier in South Korea. However, maximum load and load-time history graph showed different depending on parameters under vehicle impact loading. Therefore, in this study, analysis according was conducted to various impact conditions such as vehicle mass and impact velocity under same impact severity. Obtained results from load-time history graph showed key parameter is velocity compared to vehicle mass.

New multiband BVRI light curves of NSVS 1461538 were obtained as a byproduct during the photometric observations of our program star PV Cas for three years from 2011 to 2013. The light curves indicate characteristics of a typical W-subtype W UMa eclipsing system, displaying a flat bottom at primary eclipse and the O’Connell effect, rather than those of an Algol/ b Lyrae eclipsing variable classified by the northern sky variability survey (NSVS). A total of 35 times of minimum lights were determined from our observations (20 timings) and the SuperWASP measurements (15 ones). A period study with all the timings shows that the orbital period may vary in a sinusoidal manner with a period of about 5.6 yr and a small semiamplitude of about 0.008 day. The cyclical period variation can be interpreted as a light-time effect due to a tertiary body with a minimum mass of 0.71 M⊙. Simultaneous analysis of the multiband light curves using the 2003 version of the Wilson- Devinney binary model shows that NSVS 1461538 is a genuine W-subtype W UMa contact binary with the hotter primary component being less massive and the system shows a low mass ratio of q(mc/mh)=3.51, a high orbital inclination of 88.7°, a moderate fill-out factor of 30 %, and a temperature difference of ΔT=412 K. The O’Connell effect can be similarly explained by cool spots on either the hotter primary star or the cool secondary star. A small third-light corresponding to about 5 % and 2 % of the total systemic light in the B and V bandpasses, respectively, supports the third-body hypothesis proposed by the period study. Preliminary absolute dimensions of the system were derived and used to look into its evolutionary status with other W UMa binaries in the mass-radius and mass-luminosity diagrams. A possible evolution scenario of the system was also discussed in the context of the mass vs mass ratio diagram.

Generating motion of center of mass for biped robots is a challenging issue since biped robots can easily lose balance due to limited contact area between foot and ground. In this paper, we propose force control method to generate high-speed motion of the center of mass for horizontal direction without losing balancing condition. Contact consistent multi-body dynamics of the robot is used to calculate force for horizontal direction of the center of mass considering balance. The calculated force is applied for acceleration or deceleration of the center of mass to generate high speed motion. The linear inverted pendulum model is used to estimate motion of the center of mass and the estimated motion is used to select either maximum or minimum force to stop at goal position. The proposed method is verified by experiments using 12-DOF torque controlled human sized legged robot.

Frequency-adaptive Lumped Mass Stick (LMS) method has been proposed recently to present the dynamic responses of a structure by a stick model which has identical frequencies to the original structure. The masses of the LMS model are obtained by an iterative method following a sequence of equations, where the masses always converge to certain values. Those values are solutions of a nonlinear equations system as will be shown in this study. This paper also investigates the significance of masses locations on the dynamic responses of the LMS models.

This paper investigated the thermal and mechanical properties of high-volume fly ash concrete for potential application in mass concrete.

The analytical method for 16 organophosphorus pesticides was developed in this study. The 16 organophosphorus pesticides were analyzed by liquid chromatography-tandem mass spectrometry (LC/MS/MS) using on-line solid phase extraction (on-line SPE) with PLRP- S cartridge. Analysis of all analytes in the MS/MS was processed in the electrospray ioni-zation (ESI) positive mode. They are Azinphos ethyl, Chlorfenvinphos, Ethion, Famphur, Phosmet, Phosphamidon, Terbufos, Aspon, Chlorpyrifos-methyl, Crotoxyphos, Dichlofenthi-on, Dicrotophos, Fonofos, Thionazin, Dimethoate and Iprobenfos. Limits of detection (LODs) and Limits of quantification(LOQs) were obtained as 0.8~2.0 ng/L and 2.6~6.4 ng/L, respectively. All compounds were not detected at the 8 sampling points of the raw water and clean water.

In this study, a new idea for developing a space scale for measuring mass in a microgravity environment was proposed by using the inertial force properties of an object to measure its mass. The space scale detected the momentum change of the specimen and reference masses by using a load-cell sensor as the force transducer based on Newton’s laws of motion. In addition, the space scale calculated the specimen mass by comparing the inertial forces of the specimen and reference masses in the same acceleration field. By using this concept, a space scale with a capacity of 3 kg based on the law of momentum conservation was implemented and demonstrated under microgravity conditions onboard International Space Station (ISS) with an accuracy of ±1 g. By the performance analysis on the space scale, it was verified that an instrument with a compact size could be implemented and be quickly measured with a reasonable accuracy under microgravity conditions.

This study reviewed sulfuric acid resistance of high acid resistance of inorganic binder based on industrial by-products. As the results of test, the mix of high acid resistance of inorganic binder showed the excellent chemical resistance against aqueous solution of 10% H2SO4 comparing to the mix of OPC, however, the mass of inorganic binder rather increased while approximately 3.4% of mass loss ratio appeared during 7 days of material age of soaking in case of using portland cement usually.

Marine mass concrete mixture for floating structures is derived that can minimize heat of hydration and several construction methods are investigated to reduce thermal cracks. Analysis variables are type and amount of mineral admixtures, number of lifts and placing interval. Probability of thermal crack occurrence is evaluated.

이 글은 바흐의 세속칸타타를 담론의 중심으로 끌어들이려는 노력의 일환으로 기획된 것 이다. 이를 위해 이 글은 1733년을 주목한다. 바흐담론에서 1733년은 바흐의 《1733년 미 사》가 작곡되고 이것이 드레스덴 궁정에 헌정된 해로 기억되고 있다. 그러나 바흐담론은 이 시기 바흐가 모두 5곡의 세속칸타타를 작곡하였고, 이들 역시 드레스덴 궁정에 헌정되었다 는 사실을 과소평가하고 있다. 이 글이 시도하는 것이 이러한 기존의 시각에서 종교와 세속 의 날선 구분을 잠시 내려놓은 채 이것을 넘어선 바흐의 일상을 재구성하는 일이다. 이는 바 흐의 세속칸타타(또는 그의 《1733년 미사》)를 작곡가의 ‘특별한 과외 활동’으로 간주하지 않고, 그의 음악활동의 일상으로 이해하려는 노력이며 또한, 이것은 드레스덴을 향한 바흐의 동경, 또는 야심이 그의 대표작인 《1733년 미사》뿐 아니라 이 시기 작곡된 그의 세속칸타 타들을 통해서도 일관되게 구현되었다는 것을 말하려는 시도이기도 하다.

Spontaneous rupture of the carotid artery is rare, however, it is a fatal injury and early diagnosis is very important. We expe-rienced a 54-year-old male patient who presented to the emergency department with an expanding neck mass after cough. Rupture of the common carotid artery 2 cm before bifurcation with a pseudoaneurysm was diagnosed on neck computed tomography angiography. Focal tear of the artery was repaired surgically with suture. Herein, we report on a rare occurrence of a spontaneous carotid artery rupture and review other reports.

This study investigates weekday/weekend characteristics of PM10 and PM2.5 concentration and metallic elements in Busan in the springtime of 2013. PM10 concentration on weekday/weekend were 77.54 and 67.28 ㎍/㎥, respectively. And PM2.5 concentration on weekday/weekend were 57.81 and 43.83 ㎍/㎥, respectively. Also, PM2.5/PM10 concentration ratio on weekdays/weekend was 0.75 and 0.65, respectively. The contribution rates of Na to total metallic elements in PM10 on weekday/weekend were 38.3% and 38.9%, respectively. It would be useful in control effectively with management of urban fine particle to understand characteristics of fine particle concentration on weekday/weekend.

We present a by-product of our long term photometric monitoring of cataclysmic variables. 2MASS J18024395 +4003309 = VSX J180243.9 +400331 was discovered in the field of the intermediate polar V1323 Her observed using the Korean 1-m telescope located at Mt. Lemmon, USA. An analysis of the two-color VR CCD observations of this variable covers all the phase intervals for the first time. The light curves show this object can be classified as an Algol-type variable with tidally distorted components, and an asymmetry of the maxima (the O’Connell effect). The periodogram analysis confirms the cycle numbering of Andronov et al. (2012) and for the initial approximation, the ephemeris is used as follows: Min I. BJD = 2456074.4904+0.3348837E . For phenomenological modeling, we used the trigonometric polynomial approximation of statistically optimal degree, and a recent method “NAV” (“New Algol Variable”) using local specific shapes for the eclipse. Methodological aspects and estimates of the physical parameters based on analysis of phenomenological parameters are presented. As results of our phenomenological model, we obtained for the inclination i=90°, M1=0.745M◉, M2=0.854M◉, M=M1+M2=1.599M◉, the orbital separation a=1.65·109m=2.37R◉ and relative radii r1=R1/a=0.314 and r2=R2/a=0.360. These estimates may be used as preliminary starting values for further modeling using extended physical models based on the Wilson & Devinney (1971) code and it's extensions

Atmospheric aerosol particles were investigated at GNTECH university in Jinju city. Samples were collected using the Nanosampler period from January to December 2014. The Nanosampler is a 6 stage cascade impactor(1 stage : > 10 μm, 2 stage : 2.5~10 μm, 3 stage : 1.0~2.5 μm, 4 stage : 0.5~1.0 μm, 5 stage : 0.1~0.5 μm, back-up : < 0.1 μm) with the stages having 50% cut-off ranging from 0.1 to 10 μm in aerodynamic diameter. The mass size distribution of Atmospheric aerosol particles was unimodal with peak at 1.0~2.5 μm or 0.5~1.0 μm. The annual average concentrations of TSP, PM10, PM2.5, PM1, PM0.5 and PM0.1 were 44.0 μg/m3, 40.3 μg/m3, 31.4 μg/m3, 18.0 μ g/m3, 8.2 μg/m3, 3.0 μg/m3, respectively. On average PM10, PM2.5, PM1, PM0.5 and PM0.1 make up 0.91, 0.70, 0.41, 0.19 and 0.07 of TSP, respectively. The annual average of PM2.5/PM10 ratio was 0.77.

This study presents the concept of a multi-functional Tuned Mass Damper (TMD) using piezocomposite element as damping component. This new type of TMD intends to exploit the unused energy produced by the traffic-induced vibrations of the bridge structure for the generation of electric power while fulfilling its natural role of reducing undesirable vibrations in the structure. Since the proposed TMD is still in a development stage, this paper summarizes the concept underlying the mechanism of the TMD.

산악지형이 많은 우리나라의 지형적 특성상 터널은 장대화, 대단면화 되어 가고 있으며 다양한 암반을 관통하여 시공된다. 특히 도로, 철도 터널의 시종점부는 암반 구성 조건이 상부로부터 붕적토, 풍화암, 연암 등으로 구성되며 아칭 효과(Arching Effect)를 많이 기대할 수 없어 보조, 보강 공법을 적용한다. 따라서 안정한 시공을 위해 터널 시공 전에 수치 해석을 실시하여 보강 여부, 범위를 검토한 후 실제 시공 중에 발생한 변형, 응력 등 계측 결과와 수치 해석 결과를 서로 비교 검토(Feed Back) 하는 과정이 필요하다. 본 연구에서는 비교적 얕은 토피고를 갖는 풍화암 지반의 터널 시종점부에 대한 유한요소해석(Finite Element Analysis, FEA)과 실제 시공 중에 계측한 결과를 비교하여 터널의 안정성 여부를 최종 확인하였다.

The uneven mass distribution of the Moon highly perturbs the lunar spacecrafts. This uneven mass distribution leads to peculiar dynamical features of the lunar orbiters. The critical inclination is the value of inclination which keeps the deviation of the argument of pericentre from the initial values to be zero. Considerable investigations have been performed for critical inclination when the gravity field is assumed to be symmetric around the equator, namely for oblate gravity field to which Earth’s satellites are most likely to be subjected. But in the case of a lunar orbiter, the gravity field of mass distribution is rather asymmetric, that is, sectorial, and tesseral, harmonic coefficients are big enough so they can’t be neglected. In the present work, the effects of the first sectorial and tesseral harmonic coefficients in addition to the first zonal harmonic coefficients on the critical inclination of a lunar artificial satellite are investigated. The study is carried out using the Hamiltonian framework. The Hamiltonian of the problem is cconstructed and the short periodic terms are eliminated using Delaunay canonical variables. Considering the above perturbations, numerical simulations for a hypothetical lunar orbiter are presented. Finally, this study reveals that the critical inclination is quite different from the critical inclination of traditional sense and/or even has multiple solutions. Consequently, different families of critical inclination are obtained and analyzed.

Ambient particulate matters(PM10 and PM2.5) were investigated at GNTECH university in Jinju city. Samples were collected using a dichotomous sampler(series 240, Andersen Corp.) and a TEOM(Tapered Element Oscillating Microbalance) monitor period from November 2012 to October 2013. For the dichotomous sampler measurements, daily 24-h integrated PM2.5 and PM10–2.5 ambient air samples were collected at a total flow rate of 16.7 L /min. For the TEOM monitor measurements, daily 1-h integrated PM10 ambient air samples were collected at a flow rate of 16.7 L /min. The annual average concentrations of PM10-2.5 and PM2.5 by a dichotomous sampler were 10.0±6.1 μg/m3 and 22.6±9.3 μg/m3, respectively. And PM10 concentration by dichotomous sampler were similar to TEOM monitor by 32.7±12.9 μg/m3 and 31.7±11.3 μg/m3, respectively. And good correlation (R2=0.964) between the two methods was observed. The annual average of PM2.5/PM10 ratio was 0.70±0.12.

Vertical pipe cooling method was developed for the thermal cracking control of vertically long and slender mass concrete member. This method was applied to mass concrete wall, and the performance of this method was investigated.