The purpose of this study was to find whether hemline cycles exist and whether hemlines show greater within-year variability over time. Utilizing US Vogue data from 1950 to 2013 on hemline length of women's daywear, total 2102 day-dresses or skirts on full fashion pictures were analyzed. The skirt length was divided by the total length of figure in the picture which was measured from shoulder to ankle. Aggregated yearly means smoothed by means of three-point moving averages were used to provide a better indication of the long-term direction of movement of the hemline. Within-year hemline variability was smoothed by the way of three-point moving average as well. The data showed five cycles on hemline change processes. The first cycle took 21 years from 1950 to 1971, which was the longest period and had the biggest hemline changes. The second cycle was the shortest from 1971 to 1977, in which hemline moved between below-knee length and midcalf. The hemline in the third cycle moved between midcalf and miniskirt. The third cycle took 16 years from 1977 to 1993. The forth was a short cycle from 1998 to 2001, and hemlines moved moderately between below-knee length and above-knee length. The fifth cycle has been on going since 2001, and the hemline has been getting longer after 2007. The within-year variability of hemlines was bigger in 1980s than previous years and was steadily increased.

Shrimp beam trawl fishery is one of the important coastal fisheries in Korea. It has a regulation to the length of beam (8m) and wing net (7m) of shrimp beam trawl that has been used in the district of Junlanam-do and Gyungsangnam-do. This regulation was made in relation to the size of shrimp beam trawler of 3-ton class at that time. Now the shrimp beam fishing vessel has a limit not greater than 5 tons in gross ton. Recently, with improvement of fishing industry and fishing vessel fishermen asked the expansion of the length of beam and wing net, therefore it is necessary to investigate the effect of lengthening the beam and wing net length. Three different beams (8m, 10m and 12m in length) and three different wing net (7m, 10m and 13m in length) were made and the experiment was conducted near Narodo of Goheng by two fishing vessels of 4.98 and 4.88 tons in gross ton between June 2011 and October 2012. When the length of wing net was increased from 7m to 10m and 13m, the relative catch ratio in total biomass was increased 25% and 79% for shrimp, (17% and 22% in total), respectively. And when the beam length was increased from 8m to 10m and 12m, the relative catch ratio was increased 35% and 84% for shrimp, (21% and 37% in total), respectively. The force exerted to the iron guide of inhauler’s with the beam length of 8m was about 30% greater than that with the beam length of 10m when hauling the shrimp beam trawl net.

The plastic hinge region of RC pier ensures its nonlinear behavior during strong earthquake events. It is assumed that the piers secure sufficient strength and ductility in order to prevent the collapse of the bridge during strong earthquake. However, the presence of a lap-splice of longitudinal bars in the plastic hinge region may lead to the occurrence of early bond failure in the lap-splice zone and result in significant loss of the seismic performance. The current regulations for seismic performance evaluation limit the ultimate strain and displacement ductility considering the eventual presence of lap-splice, but do not consider the lap-splice length. In this study, seismic performance test and analysis are performed according to the cross-sectional size and the lap-splice length in the case of longitudinal bars with lap-splice located in the plastic hinge region of existing RC bridge columns with circular cross-section. The seismic behavioral characteristics of the piers are also analyzed. Based upon the results, this paper presents a more reasonable seismic performance evaluation method considering the lap-splice length and the cross-sectional size of the column.

Gemini type of cationic surfactant, namely α,ω-alkane-bis(N-lauroyloxyethyl -N,N-dimethyl)-diammonium bromide was synthesized and confirmed by FT-IR and 1H-NMR spectroscopy. Their inhibition effect on corrosion of mild steel in 1 M HCl solution was tested by weight loss method. Surface tensions were measured by surface tensiometer Sigma 70. Their c.m.c. values evaluated by surface tension method was 4.01×10-5∼ 4.99×10-5 mol/L. The Krafft point of the these surfactants were < 0 ℃. The emulsifying properties of synthesized cationic gemini surfactants and sodium dodecyl sulfate (SDS), tetradecyl trimethyl ammonium bromide (TTAB) was investigated. Of these, α,ω-alkane-bis(N-lauroyloxyethyl-N,N-dimethyl)- diammonium bromide has been confirmed as a good emulsifier. The inhibition efficiency increases by increasing cationic gemini surfactant concentration. As a result, these surfactants are expected to be applied as corrosion inhibitors.

폴리이미드 기체 분리막의 기체 분리 성능을 향상시키기 위해서 2,3,5,6-Tetramethyl-1,4-phenylenediamine (TMPD) 구조를 지닌 폴리이미드를 1,2-Diaminoethane (DAE)과 1,6-Diaminohexane (DAH)으로 가교시켜 분리막을 제조하였다. Fourier transform infrared spectroscopy (FT-IR)를 이용해 가교 후 이미드 고리가 아미드 그룹으로 전환됨을 확인하였다.폴리이미드의 열분해 온도는 가교 후 감소하였으며, 이는 가교제의 알킬기 분해 때문이다. 가교된 폴리이미드 분리막의 d-spacing은 가교 시간이 증가함에 따라 감소하였다. 가교 후 CH4, N2, O2, CO2 기체의 투과도는 가교 전 보다 감소하였으며,DAH로 가교된 분리막이 DAE보다 더 높은 투과도를 나타냈다. 투과도와 달리 CO2/CH4, CO2/N2, O2/N2 기체 선택도 모두 가교 시간이 길어질수록 증가된 결과가 나타났다. CO2/CH4 기체의 선택도는 DAE로 6분 가교 시 최대 증가치를 나타냈으며 39.5%까지 증가하였다. O2/N2 선택도 또한 DAE로 6분 가교 시 최대 증가치를 가지며 20.5%까지 증가하였다. 이를 통해서DAE가 DAH보다 선택도 증가에 적합한 가교제임을 예상할 수 있으며 이와 달리 CO2/N2 선택도는 DAE로 3분 가교 시 감소해 CO2/N2 분리에는 적합하지 않은 결과가 나타났다.

In this study, the property of crack growth in structural steel is investigated according to length and angle of crack at the analysis result of model. Strain energy, deformation and stress obtained by finite element analysis are compared with various configuration of crack. Stress intensity factors as fracture toughness are calculated by the basis of strain energy, deformation and stress. As there are almost no errors by comparing stress intensity factors with those from the standard formula, these calculated factors can be confirmed in order to be applied at real structure. In case cracks or holes at structure are existed, the fatigue damage possibility can be examined by use of this study result.

The purpose of this study is to determine more variables in welding characteristics of ATOS(steel for automobile structure) 80 high tensile steel available in market, and in terms of welding using GMAW(gas metal arc welding), this study seeks to examine how welding characteristics of ATOS 80 may vary depending on protrusion length of wire electrode. The major characteristics of this study can be summed up as follows, this study analyzed welding characteristics of ATOS 80 by changing the protrusion length of wire electrode (10㎜, 15㎜ and 20㎜) in welding section, and also used visual inspection and radiograph test to examine observations of major defects on welding section.

목적 : 본 연구는 편마비성 뇌성마비 환아들의 편마비측 상지길이 단축의 정도를 평가하고, 길이 단축과 근경직도 및 운동기능과의 연관성을 알아보고자 하였다. 연구방법 : 30명의 편마비성 뇌성마비 환아(남아 13명, 여아 17명, 평균연령 6세 4개월)와 17명의 대조군(남아 9명, 여아 8명, 평균연령 6세 2개월)을 대상으로 하였다. 상지의 상완골,척골, 요골, 두 번째와 다섯 번째 중수골의 길이를 단순방사선 촬영을 통하여 길이 측정을 하였고, 건측(대조군에서는 우성측) 대비 편마비측(대조군에서는 비우성측)의 단축의 정도는 백분율로 나타내었다. 근경직도는 Modified Ashworth Scale (MAS)를 이용하였고, 상지의 운동기능은 Quality of Upper Extremity Skills Test (QUEST)를 사용하였다. 결과 : 대조군에 비하여 환자군에서는 편마비측 상지길이의 백분율이 의미있게 단축되어 있었다(p<.05). 이러한 상지길이의 단축 정도와 근경직도의 증가 및 운동기능의 저하는 의미있는 연관성을 보였다(p<.05). 결론 : 편마비성 뇌성마비 환아에서 보이는 편마비측 상지길이의 단축은 근경직 및 운동기능과 의미있게 연관되어 있다. 추후 이러한 환아들에게서 근경직도의 완화 및 운동기능의 향상을 도모하는 재활치료 후 변화되는 상지길이의 단축 정도를 연구한다면 재활치료의 효과를 좀더 객관적으로 증명하고, 치료의 방법과 정도를 정립하는데 도움이 될 것이다.

최근 선박 대형화 추세가 급격하게 진전된 반면 국내 무역항의 수역시설 조건은 과거와 동일하여 특정 항로에서의 해상교통 혼잡이 발생할 개연성이 매우 높다. 국내항의 해상교통혼잡도를 평가하기 위해 사용하는 표준 선박길이는 70 m로, 30년 전부터 현재까지 그대로 사용하고 있어 이에 대한 검토가 시급하다. 본 연구에서는 국내 Port-MIS 데이터베이스에 저장된 60,000여척 선박 주요 제원을 기반으로 선박 대형화 추세를 분석하고, 최근선박의 총톤수와 선박 길이와의 상관함수를 이용해 선박 대형화가 반영된 표준 선박길이를 제안하였다. 또한 최근 5년간 국내 무역항 이용 선박에 대한 톤수별 척수를 기초로 소형선을 제외한 누적 빈도수가 50 % 이상 차지하는 기준점을 도출해 국내항의 표준 선박길이를 제안하였고, 각 표준 선박길이는 국내 무역항의 특성을 고려하여 적용할 필요가 있다.

생물 종 다양성 및 보존에 대한 필요성은 곤충과 같은 생물 개체의 정확하고 효율적인 인식 방법에 관심을 불러 일으켰다. 특히 스마트 폰과 같은 디지털 정보가전의 발달과 보급으로 인해 영상 매체를 이용한 곤충 종의 자동인식에 대해 많은 연구가 이루어지고 있다. 본 논문은 나비 영상 인식을 위해 가지 길이 유사성 엔트로피(Branch Length Similarity Entropy)를 이용한 특징 추출 방법을 제안한다. 제안한 특징 추출 방법은 나비의 윤곽으로부터 높은 곡률을 가진 특징점들을 추출한 다음 이들 사이를 네트워크로 구성하고 특징점 간의 길이 분포를 엔트로피로 표현한 것이다. 제안한 특징 추출 방법의 성능을 평가하고자 15종의 나비 영상을 대상으로 지도학습 기반 기계학습 방법인 베이지안 분류기, 인공 신경망 및 서포트 벡터 머신을 이용해 기존에 제시된 퓨리에 기술자 및 웨이블릿 기술자와 비교하였다.

This study investigated characteristics of buckling load and effective buckling length by member rigidity of dome-typed space frame which was sensitive to initial conditions. A critical point and a buckling load were computed by analyzing the eigenvalues and determinants of the tangential stiffness matrix. The hexagonal pyramid model and star dome were selected for the case study in order to examine the nodal buckling and member buckling in accordance with member rigidity. From the numerical results, an effective buckling length factor of adopted models was bigger than that of Euler buckling for the case of fixed boundary. These numerical models indicated that the influence of nodal buckling was greater than that of member buckling as member rigidity was higher. Besides, there was a tendency that the bifurcation appeared on the equilibrium path before limit point in the member buckling model.

목적: 누진굴절력렌즈의 피팅을 위하여 습관적인 독서자세에서 측정한 누진대 길이의 분포를 알아보았다. 방법: 2010년 1월부터 2012년 6월까지 39~83세의 남녀 5,925명을 대상으로 Eye Move Photographing (EMP)을 이용하여 누진대 길이를 측정하였고, 연령대별 분포를 분석하였다. 결과: 측정된 누진대 길이(아이포인트에서 근용부 측정점까지) 분포는 10~11mm(34.45%), 12~13mm (32.66), 8~9mm(16.96%), 14~15mm(10.13%), 6~7mm(4.30%), 16~17mm(1.27%), 그리고 18~19mm (0.25%)로 나타났다. 39~49세에서는 10~11mm가 42.05%로 가장 많은 비율이었고, 50~59세, 60~69세, 그리고 70~83세에서는 12~13mm가 각각 31.84%, 35.48%, 그리고 46.15%로 가장 많은 비율이었다. 결론: 안경실무 종사자들은 습관적 독서자세에서 정확한 누진대 길이를 측정할 수 있는 진보적인 방법 들을 계속적으로 고안할 필요가 있다.

It is known that seismic performance of existing bridges having insufficient lateral confinements and lap-splices of longitudinal reinforcements at the base of column decreases dramatically. In this study, small-scaled model tests have been performed to confirm the seismic behaviors of RC bridge piers with various lap-splice lengths. The 8 test models have circular section with diameters of 0.65 m, 0.8 m, 1.0 m, and lap-splice lengths of B-class or C-class. The test results show that the failure modes of models are not depending on the lap-splice length itself but depend on the ratio of lap-splice length to diameter, and that the displacement ductility is also affected by this ratio.

A net-assembling company for gill net fishing gears makes a design based on the size of nets provided and determines floats, types of weights, and numbers. In addition, through the accurate examination of net weights in the process of fishing gear designing, it can prevent an excessive use of designing costs. The weight of twine can be easily calculated by its thickness differences, but the weight of netting has errors to be calibrated since the weight of netting is not changing exponentially with the changes of number and size of meshes. This study aims to suggest and empirically analyze the methods for estimating the weights of netting in accordance with the changes of number, size and thickness of meshes for a sound management of netting and net-assembling companies. Results indicated that the method using the knots and legs of netting was not practically usable because the errors were increased as the number of mesh increased. However, the method using netting area shown its usage potentiality with the calibration of the increasing ratio of mesh numbers.

This study was analyzed the characteristics of temperature distribution in DPF(Diesel Particulate Filter) equipped with partitioned electric heaters. Analysis parameters was used by variation to the length of pipe from exhaust manifold to inlet of filter. The temperature of the exhaust gas flowing into the DPF is related closely to the regeneration of filter. Due to space constraints, the DPF have inlet of bent pipe. The inlet of bent pipe induce the heterogeneous distribution of flow. The heterogeneous trapping of smoke is induced according to the heterogeneous distribution of flow. And the heterogeneous distribution of temperature in DPF is induced. In this study, without the use of assistive devices for even distribution of flow into DPF, the characteristics of temperature distribution in DPF were investigated according to the variation of the length of inlet pipe.