• Journal of the Korean Society for Precision Engineering
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• v.25 no.1
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• pp.79-84
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• 2008

For the precision measurement of industrial products, the location of holes inside the products, if they exist, are often selected as feature points. The measurement of hole location would be performed by vision and laser-vision sensor. However, the usage of those sensors is limited in case of big change of light intensity and reflective shiny surface of the products. In order to overcome the difficulties, we have developed a hole displacement measuring device using contact-type displacement sensors (LVDTs). The developed measurement device attached to a robot measures small displacement of a hole by allowing its X-Y movement due to the contact forces between the hole and its own circular cone. The developed device consists of three plates which are connected in series for its own function. The first plate is used for the attachment to an industrial robot with ball-bush joints and springs. The second and third plates allow X-Y direction as LM guides. The bottom of the third plate is designed that various circular cones can be easily attached according to the shape of the hole. The developed system was implemented for its effectiveness that its measurement accuracy is less than 0.05mm.

• Journal of Periodontal and Implant Science
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• v.28 no.2
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• pp.193-203
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• 1998

20 Subjects with clinical diagnosis of adult periodontitis with sites having average pocket depth of 4mm were selected for the study. After scaling and root planing of those sites, 30% minocycline-HCI contained in biodegradable device were inserted in one group, scaling and root planing was carried out in another group and the last group was without any periodontal treatment. the difference between the group was detemined by pocket dept, bleeding on prbing, attachment level, distribution of subgingval plaque bacteria. Conclusion was made for the comparisons between baseline and 4 week and the groups. 1. In analysis of pocket depth, there was significant sifference in scaling and root planing group only. 2. Both the scaling and root planing group and minocycline group showed significant decrease in bleeding on probing. 3. There was significant increase in the attachment level in scaling and root planing group, but no difference was foundbetween the groups. 4. There was significant decrease in the total number of subgingival bacteria in all groups and the number of motile bacteria decreased significantly in the minocycline group. These result indicate that insertion of Minocycline-HCI at the base of periodntal pocket was useful as an additional aid of mechanical trarment at the point of periodontal pocket, bleeding on probing, attachment level, microbial distribution.

• Asia pacific journal of information systems
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• v.19 no.1
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• pp.113-145
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• 2009

Recently, due to the globalization of the IT(Information Technology) market, devices and systems designed in one country are used in other countries as well. This phenomenon is becoming the key factor for increased interest on cross-cultural, or cross-national, research within the IT area. However, as the IT market is becoming bigger and more globalized, a great number of IT practitioners are having difficulty in designing and developing devices or systems which can provide optimal experience. This is because not only tangible factors such as language and a country's economic or industrial power affect the user experience of a certain device or system but also invisible and intangible factors as well. Among such invisible and intangible factors, the cultural characteristics of users from different countries may affect the user experience of certain devices or systems because cultural characteristics affect how they understand and interpret the devices or systems. In other words, when users evaluate the quality of overall user experience, the cultural characteristics of each user act as a perceptual lens that leads the user to focus on a certain elements of experience. Therefore, there is a need within the IT field to consider cultural characteristics when designing or developing certain devices or systems and plan a strategy for localization. In such an environment, existing IS studies identify the culture with the country, emphasize the importance of culture in a national level perspective, and hypothesize that users within the same country have same cultural characteristics. Under such assumptions, these studies focus on the moderating effects of cultural characteristics on a national level within a certain theoretical framework. This has already been suggested by cross-cultural studies conducted by scholars such as Hofstede(1980) in providing numerical research results and measurement items for cultural characteristics and using such results or items as they increase the efficiency of studies. However, such national level culture has its limitations in forecasting and explaining individual-level behaviors such as voluntary device or system usage. This is because individual cultural characteristics are the outcome of not only the national culture but also the culture of a race, company, local area, family, and other groups that are formulated through interaction within the group. Therefore, national or nationally dominant cultural characteristics may have its limitations in forecasting and explaining the cultural characteristics of an individual. Moreover, past studies in psychology suggest a possibility that there exist different cultural characteristics within a single individual depending on the subject being measured or its context. For example, in relation to individual vs. collective characteristics, which is one of the major cultural characteristics, an individual may show collectivistic characteristics when he or she is with family or friends but show individualistic characteristics in his or her workplace. Therefore, this study acknowledged such limitations of past studies and conducted a research within the framework of 'theoretically integrated model of user satisfaction and emotional attachment', which was developed through a former study, on how the effects of different experience elements on emotional attachment or user satisfaction are differentiated depending on the individual cultural characteristics related to a system or device usage. In order to do this, this study hypothesized the moderating effects of four cultural dimensions (uncertainty avoidance, individualism vs, collectivism, masculinity vs. femininity, and power distance) as suggested by Hofstede(1980) within the theoretically integrated model of emotional attachment and user satisfaction. Statistical tests were then implemented on these moderating effects through conducting surveys with users of four digital devices (mobile phone, MP3 player, LCD TV, and refrigerator) in three countries (US, Germany, and Russia). In order to explain and forecast the behavior of personal device or system users, individual cultural characteristics must be measured, and depending on the target device or system, measurements must be measured independently. Through this suggestion, this study hopes to provide new and useful perspectives for future IS research.

• Journal of the Ergonomics Society of Korea
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• v.36 no.4
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• pp.281-292
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• 2017

Objective: This study aims to identify important physical design variables in designing a necklace type wearable device, and to present design guidelines to maximize comfort that a user feels upon wearing the device. Background: Interests in fitness culture and personal health are on the rise recently. In such a situation, demand for necklace type wearable devices is projected to increase a lot, as the devices enable users to use their hands freely and to enjoy various contents through connection with mobile devices. However, the necklace type wearable device's comfort was assessed to have the lowest comfort in a running situation, where human body moves up and down and left and right more than other devices wearable on other human body parts. Therefore, the usability of a necklace type wearable device was low. In this regard, studies on identification of the variables affecting user comfort upon wearing a necklace type wearable device and on physical design direction maximizing comfort and usability are needed. Method: A pretest and a main test were carried out to draw the direction of necklace type wearable device design. In the pretest, wearing evaluation on the diverse types of devices released in the market was conducted to draw physical design variables of the devices affecting comfort. Furthermore, variables significantly affecting the comfort of a device were selected through an analysis of variance (ANOVA). In the main test, anthropometry was performed, and information on anthropometric items corresponding to the design variables selected in the pretest was acquired. Based on the pretest results and the anthropometric information in the main test, the present study produced design guidelines maximizing the comfort of a necklace type wearable device with regard to major design variables upon dynamic tasks. Results: According to the pretest results, the variables having effects on comfort were the angle of side points, width, and height. Due to interactions between variables, those need to be simultaneously considered upon designing a device. Upon dynamic tasks, the angle of side points and width of a device was designed to be smaller than mean angle of the trapezius muscle and neck width, and thus attachment to human body was high. As height was designed to be larger than mean neck front and rear point width, comfort was higher due to feeling of stability. Conclusion: Because user sensitivity to comfort was high at human body's inflection points, a device needs to be designed for users not to feel high pressure on specific body parts with the device fitting human body shape well. A design considering user's situation is also required in further studies.

• Journal of Biomedical Engineering Research
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• v.30 no.1
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• pp.23-33
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• 2009

It can be used easily to reduce rehabilitation and treatment time if diagnostic and therapeutic devices are attached to cloth or body. Therefore we developed neuromuscular wearable ultra-miniature lighting modules which can improve the neuromuscular function and verified its clinical effectiveness. The system is based on the ultra-miniature lighting treatment module and there are two types of systems. One of them is designed as an attached type and the other type is combined with clothing. The wearable ultra-miniature lighting module is composed of controller (battery, MCU, bidirectional transmitter and receiver), cable, treatment medium generating device and other peripheral devices. To verify the clinical effectiveness of this device, we observed the difference of the strength of a muscle before and after 650nm and 25mW laser irradiation on the reflex point for 1 to 4 seconds. Among 48 patients having the degenerative osteoarthritis, the muscle strength before and after irradiation of laser was $21.8{\pm}7.99$ and $27.3{\pm}8.43$. According to the result, the muscle strength after treatment was significantly increased (p<0.01). To whom having difficulty in visiting to OPD(Out-Patient Department), doctors medically examine the patients and find the therapeutic point, attachment of this wearable ultra-miniature lighting module can function as self treatment (treating instrument) and treatment assist at home. If doctor can remotely control the patient and take part in treatment, the therapeutic device could contribute to prevention and care device.

• Journal of Biomedical Engineering Research
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• v.35 no.6
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• pp.203-210
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• 2014

Wearable medical device has been a resurgence of interest thanks to the development of technology and propagation of smart phone in recent years. Various types of wearable devices have been introduced and available in market. Capacitive coupled electrode which measures electrocardiogram over cloth is able to be applied wearable device. In previous approaches of capacitive electrode, they need proper pressure for stable contact of the electrode to body surface. However, wearable device that gives pressure on body surface is not suitable for long-term monitoring. In this study, we proposed adhesive polyurethane-based capacitive electrode for patch-type wearable electrocardiogram (ECG) monitoring device. Self-adhesive polyurethane make the electrode and whole system be adhered to the surface of skin without any pressure. The patch-type system is consisted of analog filter, analog-to-digital converter and wireless transmission module and designed to be attached on the body as a patch. To validate the feasibility of the developed system, we measured ECG signal in stable and active state and extracted heart rate. Therefore, we observed skin response after long-term attachment for biocompatibility of the adhesive polyurethane and adhesive strength of it. The result shows the possibility of applying the developed system for ECG monitoring in real-life.

• Applied Microscopy
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• v.39 no.2
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• pp.149-156
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• 2009

Fine structure of the dry adhesion system in the tarsal appendages of the jumping spider Plexippus setipes (Araneae: Salticidae) with examined using field emission scanning electron microscope (FESEM). The jumping spiders have the distinctive attachment apparatus for adhesion on smooth dry surface without sticky fluids. They attach to rough substrates using tarsal claws, however attachment on smooth surfaces is achieved by means of a tuft-like hair called a scopula. All eight legs have the scopulae with a pair of claws on the tip of feet, and each scopula is composed of two groups of setae that are capable of dry adhesion on smooth surface. The apex of each seta is flattened pad bearing many specialized adhesive setules on one side. The cuticular sensillae are interspersed at the dorsal surface of the seta. It has been revealed by this research that the contact area of the setule is always a triangular shape, and these cuticular surfaces are connected by the elongated stalks from the underlying setae. Moreover, adhesion between the numerous setules and the setae was prevented by the microscopic hairs, since these were interspersed on the upper side of the setae.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.1
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• pp.77-84
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• 2003

HS, Ammonia, CH$_4$, VOCs, Microorganism, Bacteria etc produced from swineries or henhouses are known to prevent the growth of livestock. Moreover, they give an unpleasant feeling to the workers. In this study, a methodology to remove odors and toxic gases by oxidation of ozone was thus accomplished. However, most ozone generators which use the atmospheric surrounding air have problems of contamination of electrode for discharge. Therefore in this work, a wire-cylinder type plasma reactor with DC voltage has been used both in a laboratory scale test and in the real swinery to solve the existing problems. About 6 cm of electrode gap could decrease the attachment of dusts, humid aerosols and other polymers, which are contained in the air. This compact designed device could produce ozone to oxidize and remove the air pollutants. But the amount of ozone was not large enough to be harmful to human Health. Also, the concentration of ozone was able to be varied by the input voltage. which makes it available for the proposed system to be installed in various kinds of pig houses. With this device, at maximum 43 mg/㎥ (20 ppm) of ozone could be produced at 40 ㎸ input voltage (consumed energy was 0.1 Wh/㎥). A program was also made in this work to calculate the optimum parameters for design of a plasma reactor in wide range of conditions.

• Journal of Korean Society of Water and Wastewater
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• v.35 no.6
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• pp.465-476
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• 2021

Scale and rust generation in water pipes is a common phenomenon when cast iron water pipes have been used for a long time. A physical water treatment device is known among various means for suppressing rust in a water pipe, and a zinc ionization device for putting zinc metal into a pipe and emitting the zinc cation into water is one of such devices. This research measured the amount of zinc ion generated, which is known to exhibit an effect of inhibiting rust and scale generation in a pipe, and examined the scale and rust inhibition effect of the ionization device installed for ground or building water supply. In the case of distilled water, the concentration of zinc ion increased by circulating water in the ionization device several times, and it was verified to be hundreds of ㎍/L, and in the case of discharging ground or tap water, it was verified to be tens of ㎍/L. In addition, a verification pipe was installed to confirm the change inside the pipe before and after installation of the zinc ionization device, and the internal condition of the pipe was observed 3 months to several years after installation. It was confirmed that the corrosion area of the surface of the pipe was no longer increased by installing a corrosion inhibitor, and if the pipe was already filled with corrosion products, the amount of corrosion products gradually decreased every year after installation. The phenomenon of fewer corrosion products could be interpreted as expanding the space in the pipe due to the corrosion product as Fe₂O₃ adhered to the inner surface of the pipe and turned into a smaller black Fe₃O₄. In addition, we found that scale such as CaCO₃ together in the corrosion by-products gradually decreased with the attachment of the ionization device.

• Journal of Information Display
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• v.6 no.2
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• pp.1-6
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• 2005

We demonstrated stability-enhanced liquid crystal (LC) displays using pixel-isolated LC mode in which LC molecules are isolated in pixel by horizontal polymer layer and vertical polymer wall. The device shows good electro-optic properties against external point or bending pressure due to the polymer structures. The polymer wall acts as supporting structure from mechanical pressure and prevents the cell gap from bending. Moreover, the polymer layer acts as an adhesive to ensure a tight attachment of the two substrates. We present herein various methods for producing polymer structures by using an anisotropic phase separation from LC and polymer composites or patterned micro-structures for stable flexible liquid crystal displays.