• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2012.11a
• /
• pp.27-28
• /
• 2012

This study is to low-temperature in using self-adhesive waterproofing sheet. Using self-adhesive waterproofing sheet is very comfortable in a waterproofing construction site. However, when self-adhesive waterproofing sheet is constructed from a low-temperature environment, there has been a attachment strength shortage. Therefore, this study on the attachment strength of self-adhesive waterproofing sheet is to investigate the low-temperature in the environment.

• Journal of the Korean Home Economics Association
• /
• v.17 no.1
• /
• pp.45-55
• /
• 1979

The purpose of this study is to investigate to what extent and how the infant's Object Attachment occurs. For this purpose, 28 mothers with their infants showing or having shown this phenomenon were interviewed. They were selected by the whole scale smpling method from 310 household -wives living at a delux Apt. in Seoul. The results are summarized as follows : 1. About 27% of the infants aged between 6 months and 6 years turned out to show this phenomenon. 2. Qulits, bed clothes, pillows and blankets, which infants have been closely contacted since their babyhood, were the major source of attachment objects. In general, these objects were proved to have soft, wasm, smooth, and glassy tactile sensation. 3.This phenomenon, in average, appeared since 13 months after birth, About 50% of the whole began to show this phenomenon between 9 and 14 month after birth. 4. Half of the infants didn't show a change of attachment strength, but as for the other half, the attachment strength increased after one year of age, and decreased after three years of age, as the social period commenced. 5. Infants needed attachment objects especially when they were driven by sleep, sense of emptiness, and monotonous or boring feeling. 6. There were little difference between Object Attachment behavior and motherinfant attachment behavior except "babbling", "using her as a base for exploration". Those behaviors did not appear in Object Attachment. 7. mothers said that their children's attachment objects played the role of substitute mother, pacificater, warmer, friend , etc. And they attributed this phenomenon's appearance to lack their physical contact with, ocnstant and warm care toward, their children or bottle feeding.

• Journal of the Korean Society of Safety
• /
• v.23 no.2
• /
• pp.14-20
• /
• 2008

The objective of this study is to examine fatigue strength of the welded details. In order to attain the goal of this study, the bending fatigue tests was performed for four kinds of welded details used in steel bridges, such as in-plane gusset, out-of-plane gusset, cruciform, and cover plate. The effect of the length of welded attachment on fatigue strength was greater in out-of-plane gusset than in in-plane gusset. The fatigue strength of welded details with short attachment was superior to that with long attachment. Fatigue strength of welded details with transversely loaded welds was lower than that with longitudinally loaded welds, and those results were not satisfied with AASHTO specifications. For the fatigue strength of cover plate, cover plate with rectangular section was superior to that with tapered section. It was found that the fatigue crack initiates at the points of stress concentration which are the boundary between the base metal and the bead of weld in the part of the longitudinal edge of attachment, and propagates first along the boundary and along the perpendicular to the direction of the principle stress in the base metal of welded tip.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2016.05a
• /
• pp.109-110
• /
• 2016

The recent introduction of Metal spraying method apply to construction and civil steel structure is increasing. In applying the metal spraying lining process of construction and civil steel structure to secure the adhesion strength between the metal thermal spray coating and the steel structure and the highest priority requirements are required bond strength test reliable measurement accordingly. In this study, by calculating the deposition intensity and the standard deviation, coefficient of variation corresponding to the bonding area, unlike the shape of the attachment we compared the results.

• Environmental Engineering Research
• /
• v.13 no.3
• /
• pp.141-146
• /
• 2008

Transport of Escherichia coli ATCC 11105 through porous media was investigated in this study using two sets of column experiments to quantify the attachment-related parameters (sticking efficiency, attachment rate coefficient and filter factor). The first set of experiments was performed in quartz sand under different ionic strength conditions (1, 20, 100, 200 mM) while the second experiments were carried out in quartz sand mixed with metal oxyhydroxide-coated sand (0, 5, 10, 25%). The breakthrough curves of bacteria were obtained by monitoring effluent, and then bacterial mass recovery and attachment-related parameters were quantified from these curves. The first experiments showed that the mass recoveries were in the range of 13.3 to 64.7%, decreasing with increasing ionic strength. In the second experiments, the mass recoveries were in the range of 15.0 to 43.4%, decreasing with increasing coated sand content. The analysis indicated that the sticking efficiency, attachment rate coefficient and filter factor increased with increasing ionic strength and coated sand content. The value of filter factor in the first experiments ranged from 1.45 e-2 to 6.72 e-2 1/cm while in the second experiments it ranged from 2.78 e-2 to 6.32 e-2 1/cm. Our filter factor values are one order of magnitude lower than those from other studies. This discrepancy can be attributed to the size of sand used in the experiment. The analysis demonstrated that the travel distance of bacteria estimated using the filter factor can be varied greatly depending on the solution chemistry and charge heterogeneity of porous media.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.29 no.3
• /
• pp.211-221
• /
• 2023

This study was conducted as a basic study for the selection of tags suitable for logistics management in the palletized unit-load unit and the development of various technologies to activate the palletized unit-load shipment of agricultural products through local APCs. Three types of passive RFID tags of UHF 900 MHz and one type of active RFID tag of 2.4 GHz band designed and manufactured through this study were used to analyze the receiving strength according to the tag's attachment location and distance of the palletized unit-load of agricultural products. In the passive RFID tag, there was a large difference in receiving strength by the tag's attachment location and a large amount of data loss depending on the distance within 30 m, whereas, in the active RFID tag, it was superior to the passive tags in terms of both receiving strength and data loss. Therefore, active tags are desirable from the perspective of multiple identification of warehouses with large spaces in relation to the application of RFID tags for palletized unit-loads of agricultural products, but the development of low-power technologies such as software wakeup power management as well as hardware to minimize battery power consumption is necessary.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2000.10a
• /
• pp.828-835
• /
• 2000

In recent years, RC structures need reinforcement due to physical and chemical deterioration, reduction of serviceability and structural capacity. For reinforcement of RC structures, steel plate attachment, area increase and composite fiber sheet attachment methods are used, but there are some problems like weight increase, workability, quality control and fire resistance capacity. This study presents the effectiveness of flexural reinforcement of RC beams using composite rods that are inserted in high strength special purposed polymer mortar.

• Journal of Families and Better Life
• /
• v.28 no.6
• /
• pp.157-167
• /
• 2010

This study examined the relationships among children's attachment to the mother, trait anger, anger expression style, and emotional-behavioral problems in children. The subjects were 384 5th and 6th graders at elementary schools in J and G cities of Jeonbuk-Do. The instruments were Revised Inventory of Parent and Peer Attachment (IPPA-R), Stat-Trait Anger Expression Inventory - Korean version (STAXI-K), and Strength and Difficulty Questionnaire (SDQ). The major results are as follows; The level of children's attachment to the mother was negatively related to anger and emotional-behavioral problems, and the level of trait anger was positively related to emotional-behavioral problems. Children who have high anger expression and anger suppression tended to show more externalized behavior problems. Finally, the regression analysis showed that children's attachment to the mother and anger are revealed as significant factors in emotional-behavioral problems.

• Applied Microscopy
• /
• v.44 no.4
• /
• pp.111-116
• /
• 2014

This study investigates the developmental pattern of adhesive discs (ADs) to highlight the ontogeny and structural changes that occur during the growth of Boston ivy. Initiation to postmortem features of ADs were examined through light and scanning electron microscopy. The study also reveals a new finding of the dislocation of peripheral tissues of adaxial origin. Four phases of attachment are suggested with regards to its climbing behavior: 1) pre-attachment, 2) upon attachment, 3) after attachment, and 4) final attachment. During initiation, several ADs originate from tendril primordia without epidermal differentiation. However, different growth rates in the epidermis results in completely different ADs. ADs were discerned by size, shape, and color during expansion, but cells in the adaxial surface remained alive longer than the other side. Upon contact, the ADs demonstrate simultaneous growth and deterioration, but once attachment is established the latter process subdues to final stages. Epidermal transformation, adhesive secretion, cellular disruption, and mechanical stress were essential for the self-clinging nature of Boston ivy. The post-attachment sequence is also believed to be critical in achieving maximum mechanical strength to provide extensive support. The developmental process of ADs is prompted by tactile stimulation but in a highly organized and systematic manner.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.18 no.4
• /
• pp.375-380
• /
• 2005

CF₄ molecular gas is used in most of semiconductor manufacture processing and SF/sub 6/ molecular gas is widely used in industrial of insulation field. but both of gases have defect in global warming. C₃F/sub 8/ gas has large attachment cross-section more than these gases, moreover GWP, life-time and price of C₃F/sub 8/ gas is lower than them, therefor it is important to calculate transport coefficients of C₃F/sub 8/ gas like electron drift velocity, ionization coefficient, attachment coefficient, effective ionization coefficient and critical E/N. The aim of this study is to get these transport coefficients for imformation of the insulation strength and efficiency of etching process. In this paper, we calculated the electron drift velocity (W) in pure C₃F/sub 8/ molecular gas over the range of E/N=0.1∼250 Td at the temperature was 300 K and gas pressure was 1 Torr by the Boltzmann equation method. The results of this paper can be important data to present characteristic of gas for plasma etching and insulation, specially critical E/N is a data to evaluate insulation strength of a gas.