• Journal of Ocean Engineering and Technology
• /
• v.1 no.1
• /
• pp.104-110
• /
• 1987

Fatigue tests by axial loading (R = 0.05) were carried out to investigate fatigue crack growth characteristics of small surface cracks in 2 1/4 Cr-1 Mo steel at room temperature by using flat specimens with a small artificial pit. All the data of the fatigue crack growth rate obtained in the present test are determined as a function of the stress intensity factor range about a semi-elliptical crack, so that the application of linear fracture mechanics to the surface fatigue crack growth and to the fatigue crack growth into depth, and all the data obtained from tests were discussed in comparison with the data of Type 304 stainless steel and two type of mild steel under the same test conditions. The obtained results are as follows: 1)When the cycle ratios are same, surface fatigue crack length and its depth are almost same and fall within a narrow scatter band in spite of different stress levels. 2)Relations of the surface fatigue crack growth rate (da/dN) and fatigue crack growth rate into depth (db/dN) to its stress intensity factor range ($\Delta K_{Ia}, \Delta K_{Ib}$) can be plotted as a straight line at log-log diagram without dependence of stress level and coincide with the data of part-through crack in various steels.

• Journal of the Korean Society of Fashion and Beauty
• /
• v.4 no.1 s.7
• /
• pp.35-41
• /
• 2006

From 1995 to 2005 the information related to clothing and textiles publicized by 6 journals regarding Elder Women's body type was collected and analyzed. The results are as follows. 1. It has been investigated into the elder woman's body type since 1995, and this subject needs a detailed study. in audition, investigation into woman's body type has been studied parts of the body for clothing construction. 2. Analysis result for measure area preponderance(Seoul area and local metropolitan city) of area, measure subject number mainly to large scale group more than 300 people that measure is consisting most know can. 3. Where the way of measurement is concerned, there are direct measurements more than indirect measurements. In case of using just direct measurement, the study often mentions necessity of indirect measurements. Therefore it is thought simultaneous measurement is the most desirable. 4. A Body type characteristic of elder woman shows a size of every part diminishes as growing older. Owing mainly to obesity of waist and abdomen, they have a changed body a measure of around the abdomen is bigger than around the hips. hips drop and the upper half of the body down, and besides, feet are changed into the flat.

• Journal of the Korean Institute of Rural Architecture
• /
• v.14 no.4
• /
• pp.37-45
• /
• 2012

The villages in island were established overcoming natural environment through Shamanism and changed by developing various industrials like transportation. Gapa Island located in southern part of Jejudo is flat topography different from the other islands. The purpose of this study is to clarify characteristics on transformation of community space in Gapa Island. For purpose, community spaces in Gapa Island are researched such as establishment, function, change, and use of community space. Spatial components in Gapa Island are like as spaces in faith, residential area, area for production, commercial zone, community space, education facilities, public offices, port, and roads. The methods of this study are literature research and interview survey for residents in Gapa Island. The results are as followings: First, community space is in charge about social, industrial, and religious function. Second, for traditional spaces separated for male and female, demarcation of space does not exist in industrial side but the demarcation has still been exist in religious side. Finally, by development of tourism new community space has been charge in festival function as well as function of space like agora for meeting with people freely, which is relatively various in function of community space in social side. Role of the dock for ship, main transportation of island, is being increasing as square.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.58 no.6
• /
• pp.1186-1193
• /
• 2009

Wearable ECG monitoring is regarded as one of the most essential part in the ubiquitous healthcare environment and subsequently day-life monitoring of a heart condition has been pursued especially for the elder people. However, there are many problems to accomplish this task such as; i) implementation of long-term monitoring device, ii) development of non-irritating electrode on skin and iii) stable signal acquisition. With these aims, we have focused on implementing a non-irritating electrode with an endurable monitoring device for day-life. To accomplish our tasks, we basically developed four different types of textile electrodes that are adapted by both shape and the composed material; flat or convex shape and Ag-conductive paste material or not. It turns out to be that a convex shape and Ag-paste textile electrode has the best performance in terms of both signal-to-noise ratio (SNR) and Impedance/Phase characteristics. Furthermore, ECG amplifier (35 ${\times}$ 35 mm) has developed to resolve the ECG signal and transfer the signal to desktop computing device or portable one by RF serial communication.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.24 no.6 s.177
• /
• pp.1565-1574
• /
• 2000

Surface edge crack subjected to contact stresses is analysed. A punch with corner radii is considered to press the semi-infinite plane. Partial slip problem is solved when a shear force is applied to the punch. Dislocation density function method is used to solve the present mixed mode crack problem. The crack length of positive K1 is examined, which is affected by the ratio of the flat portion to the total width of the punch. Surface traction during one cycle of the shear force is evaluated to simulate the fretting condition. The compliance change of the contact surface is also investigated during the shear cycle. It is found that the crack grows during only a part of the cycle, which may be termed as effective period of crack growing. A design method for restraining the fretting failure is discussed, from which recommendable geometry of the punch is suggested.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.20 no.4
• /
• pp.596-608
• /
• 1996

For design of early childhood children's footwear, this study was to analyze the properties of their foot. This study was performed in 200 male and 200 female early childhood children from 3 and 6 years old lived in susan urban area. There were measured 17 items of the foot and calculated 4 indexs for analysis. The result was as follows; 1 The growth rate differs from the sites of a foot. According to the growth of age, early childhood children's foot are more slender. 2. The average of foot print angle is $15~27^{\circ}$ and it is flat. Among the age groups, the numbers of 4 kinds of foot print angle are different siginificantly. 3. The average of metatarso phalanx angle is $174~178^{\circ}$ that is higher than adults'. 4. There are no significant difference between male children's foot and female childen's one except tarsal circumference and tarsal height. Tarsal part of male children is higher and ticket than female children's. 5. Because some of 3~6 age groups belong to the one foot length group, we should consider the age properties of foot in order to design footwears. When the size of footwear is divided by only foot length, the ranges of another measurements are larger than the range of foot length.

• Ocean and Polar Research
• /
• v.26 no.2
• /
• pp.207-218
• /
• 2004

Lomilik Seamount in the west Pacific was seismically surveyed and photographed to illuminate the bottom topography, the condition of manganese crust, and the characteristics of sedimentary environment. Lomilik Seamount has a NW-SE elongated bottom topography with steep slopes in the NESW direction part. Even though the steep slopes of the seamount are devoid of deposits, the summit area and gentle slope of the seamount are covered with thick deposits. The seismic data indicate that Lomilik Seamount is a flat-topped and step-faulted guyot of volcanic origin. Deep-sea camera photographs show that much of the seafloor is rippled in symmetrical and asymmetrical patterns. The traces of biological activity were distinct on gentle seafloor suggesting the low-energy bottom conditions. Some photographs also show outcrops encrusted with manganese crusts. Sedimentary environments in the Lomilik Seamount appear have been governed by regional morphology and strong bottom current.

• The KIPS Transactions:PartC
• /
• v.13C no.6 s.109
• /
• pp.757-766
• /
• 2006

Mobile Ad-hoc Network(MANET) is an autonomous network consisted of mobile hosts. A considerable number of studies have been conducted on the MANET with studies of ubiquitous computing. Several studies have been made on the clustering schemes which manage network hierarchically to Improve flat architecture of MANET. But the conventional schemes have the lack of multi-hop clustering and load balancing. This paper proposes a clustering scheme to support multi-hop clustering and to consider load balancing between cluster heads. We define the split of clusters and states of cluster, and propose join, merge, divide, and election of cluster head schemes for load balancing of between cluster heads

• The KIPS Transactions:PartC
• /
• v.13C no.6 s.109
• /
• pp.749-756
• /
• 2006

Broadcast nature of wireless medium and path-loss reduction create a favourable condition for collaborative communications (CC) among single-antenna users to gain the powerful benefits of multi-antenna system without the demand for physical arrays. This paper proposes a CC strategy adapting to the propagation environment changes by optimizing the transmit signal amplification factors to simplify the structure of maximum likelihood (ML) detector and to obtain the minimum error probability as well. The closed-form BER expression was also derived and compared to the simulation results to evaluate the performance of the suggested solution. A variety of numerical results revealed the cooperation significantly outperforms non-cooperative counterpart under flat Rayleigh fading channel plus AWGN (Additive White Gaussian Noise).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.11a
• /
• pp.330-331
• /
• 2006

Recently, plasma display panels (PDPs) are highlighted for the flat type display device. Therefore, much attention has been paid to secondary electron emission coefficient of the electrode protective material of PDPs. As PDPs is developing, the concern about secondary electron emission coefficient ($\gamma$) which is related with PDPs electrode protection material is increasing continually. So the concern about the way to how to measure secondary electron emission coefficient is on the rise. At present, the way to how to measure secondary electron emission coefficient is developed by some research groups, which is giving some research part's advance help. In this research, we have studied how to measure secondary electron emission coefficient which is related with various thin films more conveniently than previous measurement method. We studied the method of measurement of secondary electron emission coefficient (${\gamma}$) of amorphous silicon films by using Paschen's curve.