The purpose of this paper is to evaluate the structural performance of joints between modules with steel plate press forming type non-symmetric cross section. The main experimental variables are direction of load, whether vertical bolts are fastened, and whether the concrete inside the column is filled. A total of three experiments were performed for each variable. Experimental results show that the behavior of the joints dominated by the local buckling deformation of the upper and lower beam flanges of the module joints, and the final failure was the fracture of the column-beam welds. In case of short side direction, it is possible to secure the performance of intermediate moment frame (0.02 rad). In case of long side direction, it is evaluated that the performance of special moment frame (0.04 rad) is secured regardless of whether or not concrete is infilled in the column.

Background: Temporomandibular disorder (TMD) is characterized by pain and limited range of motion in the jaw. TMD patients generally prefer to chew on the unaffected or less-affected side, and this tendency often results in asymmetries in masseter muscle thickness and range of mandibular motion. Objects: The purpose of this study was to compare the asymmetries in masseter muscle thickness and range of mandibular motion in subjects with and without temporomandibular disorders. Methods: Thirty-nine subjects were divided into two groups: A TMD group (n1=19) and a control group (n2=20). The jaw opening range and laterotrusion were measured using a digital vernier caliper. The masseter muscle thickness was examined in both the resting state and the maximal clenching state using ultrasonography. The absolute asymmetry indices calculated based on the laterotrusion and masseter muscle thickness of the respective right and left sides. A two-way ANOVA and a Mann-Whitney U test were used for statistical analysis. Results: No significant different was found in the masseter muscle thickness between the TMD and control group. A significant difference was found in the absolute asymmetry indices of mandibular laterotrusion between the TMD and control groups (p<.05). Furthermore, the ranges of jaw opening were significantly different between males and females (p<.05). The absolute asymmetry index values of masseter muscle thickness at rest and during maximal clenching were also significantly different between males and females (p<.05). Conclusion: These results demonstrated that the subjects with TMD had a larger degree of asymmetry in laterotrusion than those without TMD. Therefore, a physiotherapy program needs to be designed to restore normal laterotrusion capacities for TMD subjects. These results also showed that female subjects had greater absolute asymmetry indices in masseter muscle thickness than male subjects. Therefore, more training is needed to promote bilaterally balanced chewing among women.

Recently developed crosslinked TR (XTR) membranes as an advanced TR material exhibit high permeability and high selectivity stemming from higher rigidity due to a simultaneous and synergetic reaction of crosslinking and thermal rearrangement. The precursor crosslinkable co-HPI precursor can be dissolved in a wide range of commercial solvents indicative of an excellent processibility. Herein, a systematic spinning process, using a newly designed crosslinkable co-HPI precursor to fabricate defect-free XTR-PBOI hollow fiber membranes with inner skin layer will be discussed based on the phase inversion kinetics of nonsolvent-induced phase separation (NIPS) method.

In this study, we investigated the dynamic stability of the system and the semi-analytical solution of the shallow arch. The governing equation for the primary symmetric mode of the arch under external load was derived and expressed simply by using parameters. The semi-analytical solution of the equation was obtained using the Taylor series and the stability of the system for the constant load was analyzed. As a result, we can classify equilibrium points by root of equilibrium equation, and classified stable, asymptotical stable and unstable resigns of equilibrium path. We observed stable points and attractors that appeared differently depending on the shape parameter h, and we can see the points where dynamic buckling occurs. Dynamic buckling of arches with initial condition did not occur in low shape parameter, and sensitive range of critical boundary was observed in low damping constants.

본 논문에서는 기능경사재료 보 고유벡터의 변화도 산정을 위한 해석 정식화를 섭동법에 기초하여 제시한다. 불확실인수로는 기능경사재료 보의 중앙면에서 보의 축을 따르는 방향으로 공간적 불확실성을 가지는 재료탄성계수를 택하였다. 두께 방향으로의 탄성계수 변화는 원래의 지수함수를 따르는 것으로 가정하였다. 정식화에서는 고유벡터에 대한 선형 Taylor전개 를 적용한다. 수치예제로는 보의 중앙면에 대하여 대칭인 탄성계수를 가지는 단순지지보를 택하였다. 몬테카를로 해석을 함 께 수행하여 제안한 정식화가 합리적인 결과를 주는지 확인하였다. 해석을 통하여 몬테카를로 해석과 제안된 방법에 의한 결과가 고유모드의 평균 및 표준편차에서 거의 동일한 결과를 제시함을 볼 수 있었다. 제안된 방법을 통하여 고유모드의 표 준편차 형상을 쉽게 산정할 수 있다. 고유모드의 평균중심 변화량은 고유모드의 차수에 관계없이 그 고유모드 대비 한 개가 더 많은 경사 0인 점을 가지게 된다. 또한 평균 고유모드형상으로부터의 변화량은 저차 모드보다 고차모드에서 더 크게 나 타남을 알 수 있었다.

Squid is a popular seafood in Korea. However, since the 2000s, the squid production has been declining. The unstable supply of the squid products may cause price fluctuations of fresh and chilled squid. These price fluctuations may be relatively more severe than them of other commodities, because the fresh and chilled squid can not be stored for a long period of time. Thus, this study analyzes the structural characteristics of price volatility and price asymmetry of fresh squid based on off-diagonal GARCH model. Data used to analysis of this study are daily wholesale and retail prices of fresh squid from January 1, 2006 to December 31, 2016 provided in the KAMIS. As theoretical approaches of this study, first of all, the stability of the time series is confirmed by the unit root test. Secondly, the causality between distribution channels is checked by the Granger causality test. Thirdly, the VAR model and the off-diagonal GARCH model are adopted to estimate asymmetry effect and price volatility spillover between distribution channels. Finally, the stability of the model is confirmed by multivariate Q-statistic and ARCH-LM test. In conclusion, fresh squid is found to have shock and volatility spillover between wholesale and retail prices as well as its own price. Also, volatility asymmetry effect is shown in own wholesale or retail price of fresh squid. Finally, this study shows that the decrease in the fresh squid retail price of t-1 period than the increase in the t-1 period has a greater impact on the volatility of the fresh squid wholesale price in t period.

본 논문은 3차원 축대칭 몰수체에 대해 소스 코드가 공개된 OpenFOAM 4.0을 이용하여 첫 번째 격자의 높이와 레이놀즈 수에 따른 마찰저항 변화에 대해 연구하였다. 마찰저항 계산을 위해 경계조건, 수치조건을 정립하였다. 축대칭 물체의 3차원 효과로 인해 거칠 기가 매우 작은 12 μΜ에서도 부드러운 표면과 비교해 마찰저항이 다르게 계산되었다. 레이놀즈 수가 커질수록 경계층의 두께 증가가 감소되었으며 이로 인해 마찰저항의 증가량이 감소되었다. 첫 번째 격자의 크기인 y+에 대한 영향에 대해서도 검토하였다. 첫 번째 격자가 log layer에 위치하고 있지 않으면 마찰저항과 표면의 전단력이 과도하게 예측되는 것을 확인하였다. 이는 경계층이 두껍게 예측되어 난류 에너지가 과도하게 예측되었기 때문으로 판단된다. 표면의 거칠기가 커질수록 경계층이 두꺼워지고 표면의 난류에너지가 증가되는 것을 확인하였다. 마찰저항을 정확하게 예측하기 위해서는 y+ 값, 거칠기 및 벽함수가 적절한 영역에 위치해야 함을 알 수 있었다.

Thermally rearranged polybenzoxazole (TR-PBO) membranes has a excellent gas separation properties due to its high fractional free volume and suitable cavity size.1) Furthermore, thermally rearranged poly(benzoxazole-co-imide) (TR-PBOI) materials show the improved mechanical strength and gas separation properties.2) In this study, TR-PBOI asymmetric hollow fiber membranes was fabricated via NIPS method. In detail, the influence of co-solvent system and polymeric additives with various molecular weight on gas separation performance was observed. For further performance optimization, dope & bore flow rate and coagulation temperature were controlled.3) The characterization on membranes was conducted by FE-SEM, pure and mixed gas permeation test with micro-GC system.

The asymmetric porous polybenzimidazole membranes were prepared to increase the doping level of phosphoric acid to increase ionic conductivity, to block the fuel/oxidant gas permeation to keep open circuit potential and to maintain chemical and mechanical stability to have good durability for proton exchange membrane fuel cells. The poly(benzimidazole) was synthesized and the asymmetric porous membranes were prepared by pore forming agents and proprietary film formation technology. As a result, it showed higher ionic conductivity, low gas permeability and similar chemical and mechanical stability.

The PBI membrane doped with phosphoric acid (PA) is one of the promising candidates for HT-PEMFC. The proton conductivity of PA doped PBI depends on the acid doping level (ADL). The method to fabricate porous PBI membrane using porogen were reported to increase the ADL. However, high ADL cause complete loss of the mechanical strength of the membranes. In this research, the dead-end porous PBI membranes were prepared using progen to increase the mechanical strength than porous PBI membrane and proton conductivity. The dead-end porous PBI membranes were investigated in terms of ionic conductivity, ADL, SEM and mechanical strength.

In this study, elastic flange local buckling strength of doubly symmetric I-girder subjected to bending moment were evaluated by 3D finite element analysis. The analysis model were modeled by 3D shell elements(S4R) using ABAQUS 6.13 program. And loading and boundary conditions were determined by equal end moments and simple boundary conditions. Flange and web slenderness ratio were considered in the parametric studies to evaluate flange local buckling strength with AISC design equations. Then, AISC design equations and characteristics of Elastic flange local buckling of I-girder were evaluated.

본 연구는 상담심리학의 성격특성이론에 근거하여 좌·우뇌의 신경학적 비대칭성 및 두뇌 각 영역에서의 활성뇌파와 성격의 요인별 특성과의 관련성을 EEG측정을 통해 알아보고자 하였다. 이에 96명의 대학생들을 대상으로 8채널 EEG 장비를 이용하여 뇌파를 측정한 후 컴퓨터로 분석한 자료와 성격 5요인 질문지를 사용하여 조사한 자료를 통계 분석하 였다. 그 결과 전전두엽의 쎄타파 좌·우뇌비대칭이 클수록 성격요인 중 신경증이 높은 것으로 나타났고, 각 두뇌영역별 로는 전전두엽좌측의 쎄타파 활성이 클수록 신경증은 높고, 성실성은 낮아지는 것으로 나타났으며, 전두엽좌측의 베타 파 활성이 클수록 외향성과 개방성이 낮아지는 것으로 나타났다. 이러한 연구결과는 두뇌영역별 특정뇌파리듬의 활성 이 개인의 성격 및 심리적 특성에 유의미한 관련이 있음을 알 수 있게 한다. 기존의 연구들 대부분이 주로 알파파, 베타파 영역에서 성격과의 관련성에 대해 언급했던 것과 달리, 본 연구결과는 세타파가 성격특성과 관련이 있을 수 있음을 시사한다. 이러한 연구 결과를 토대로 두뇌관련 상담전략과 후속연구에 대해 제언하였다.

In this study, the effect of slit length on the reduction of waste material was studied numerically. At the same time, the tightening axial force between steering shaft and asymmetry pinch yoke was also studied and compared. To achieve this study, the numerical simulation was performed by AFDEX commercial code. The slit length(Ls) of pinch yoke was increased from 25mm to 34mm by the steps with an interval of 3mm. AISI 1025 was applied for the source material of asymmetry pinch yoke. Amount of deformation was applied as much as 0.1mm for tightening the pinch bolt yoke and the steering gear shaft. It was revealed that the stress of steering shaft ear in XX-direction and YY-direction showed the highest value in 34mm and 31mm of slit length cases, respectively. The stress of ZZ-direction has the same value in all cases. The tightening stress between the asymmetry pinch yoke and the shaft of steering gear had the highest value in XY-direction. In additions, when slit length was increased by the steps with an interval of 3mm, the material was more wasted approximately as much as 0.844g. In conclusions, 31mm of lit length was the optimal length in aspect of the tightening stress and the waste material.

본 연구에서는 높은 이산화탄소 분리성능을 가지는 폴리이미드의 제조를 위해 2,2-bis(3,4-carboxylphenyl) hexafluoropropane과 두종류의 아민인 2,3,5,6-tetramethyl-1,4-phenylenediamine, Poly(ethylene glycol) bis(3-aminopropyl) terminated을 이용하여 합성을 진행하였다. 합성된 고분자를 비용매 상전이법으로 비대칭 분리막을 제조하기 위하여 고분자의 용 해도 지수 추정 값과 비용매 상전이 계수 측정을 통해 용매를 선정하였고, 고분자 용액 점도 측정을 통해 분리막 제조를 위 한 도프용액 중의 고분자의 함량을 결정하여 질산리튬을 첨가제로 사용하여 최종적으로 분리막을 제조하였다. 제조된 평판형 비대칭 분리막은 전자주사현미경(SEM)을 통해 질산리튬과 휘발성 용매 함량에 변화에 따른 모폴로지의 변화를 확인하였으 며, 이의 변화에 따른 기체 투과도 변화를 확인하였다. 분리막 제조를 위한 도프용액 중의 휘발성 용매 함량이 작을수록 선택 도 변화가 없으면서 이산화탄소 투과도가 증가하는 것을 확인하였다.

A single-layerd steel lattice roof, which has 50m span, was constructed. In order to figure out the realistic buckling load level, the structural analysis of this roof structure was performed especially by local snow load. Due to the characteristics of application of snow load, the load combinations of snow should be considered not only global area but also local part so that the critical buckling load could be observed as easy as possible. Geometrical imperfection was simulated to consider inaccurate shape of structure. And then nonlinear analysis were performed. Finally, this paper could investigate that the local snow load with geometrical imperfection decreased the level of buckling load significantly.

본 연구에서는 0.5 wt% 에멀젼형 절삭유 수용액에 평막형 분리막을 침지시키고 대칭 및 비대칭 사인파형 투과유속 연속운전(SFCO) 방식으로 실험하였다. 사용한 정밀여과막은 유효 막면적이 0.02 m2이고 공칭 세공크기가 0.15 μm이었다. 탁도 기준으로 에멀젼형 절삭유의 99% 이상이 제거되었으며 산기량이 증가할수록 TMP가 낮게 상승하였다. 비대칭형 SFCO 운전방식은 투과유속이 낮은 10∼15 L/m2·h 영역에서 대칭형 SFCO 운전방식보다 다소 유리하였다. 하지만, 투과유속이 높은 25∼30 L/m2·h에서는 대칭형 SFCO 운전이 매우 효과적임을 확인할 수 있었다.

A seismic response analysis method for three-dimensional floating offshore structures due to seaquakes is developed. The hydrodynamic pressure exerted on the structure is calculated taking into account the compressibility of the sea water, the fluid-structure interaction, the energy absorption by the seabed, and the energy radiation into infinity. To validate developed method, the hydrodynamic pressure induced by the vibration of a floating massless rigid circular disk is calculated and compared with an exact analytical solution. The developed method is applied to seismic analysis of a support structure for a floating offshore wind turbine subjected to the hydrodynamic pressures induced from a seaquake. Analysis results show that earthquake response of a floating offshore structure can be greatly influenced by the compressibility of fluid, the depth (natural frequencies) of the fluid domain, and the energy absorption capacity of the seabed.

The common features of walking in patients with stroke include decreased gait velocity and increased asymmetrical gait pattern. The purpose of this study was to identify important factors related to impairments in gait velocity and asymmetry in chronic stroke patients. The subjects were 30 independently ambulating subjects with chronic stroke. The subjects’ impairments were examined, including the isokinetic peak torque of knee extensors, knee flexors, ankle plantarflexors, and ankle dorsiflexors. Passive and active ranges of motion (ROM) of the ankle joint, ankle plantarflexor spasticity, joint position senses of the knee and ankle joint, and balance were examined together. In addition, gait velocity and temporal and spatial asymmetry were evaluated with subjects walking at their comfortable speed. Pearson correlations and multiple regressions were used to measure the relationships between impairments and gait speed and impairments and asymmetry. Regression analyses revealed that ankle passive ROM and peak torque of knee flexors were important factors for gait velocity (R2=.41), while ankle passive ROM was the most important determinant for temporal asymmetry (R2=.35). In addition, knee extensor peak torque was the most significant factor for gait spatial asymmetry (R2=.17). Limitation in ankle passive ROM and weakness of the knee flexor were major contributors to slow gait velocity. Moreover, limited passive ROM in the ankle influenced the level of temporal gait asymmetry in chronic stroke patients. Our findings suggest that stroke rehabilitation programs aiming to improve gait velocity and temporal asymmetry should include stretching exercise for the ankle joint.