• Journal of Technologic Dentistry
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• v.46 no.2
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• pp.28-35
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• 2024

Purpose: To evaluate the three-dimensional trueness of upper and lower denture bases produced using a digital light processing (DLP) printer and immersed in a constant-temperature water bath. Methods: An edentulous model was prepared and fitted with denture bases and occlusal rims manufactured using base plate wax. After scanning the model, denture bases, and occlusal rims, complete denture designs were created. Using the designs and a DLP printer, 10 upper and 10 lower complete dentures were manufactured. Each denture was scanned before (impression surface of upper denture base before constant temperature water bath [UBC] and impression surface of lower denture base before constant temperature water bath [LBC] groups) and after (impression surface of upper denture base after constant temperature water bath [UAC] and impression surface of lower denture base after constant temperature water bath [LAC] groups) immersion in the constant-temperature water bath. Scanned files were analyzed by comparing reference and scanned data, with statistical analysis conducted using the Kruskal-Wallis test (α=0.05). Results: Statistical analysis revealed no significant differences between the UBC and LBC groups, nor between the UAC and LAC groups (p>0.05). However, significant differences were observed between the UBC and UAC groups and between the LBC and LAC groups, i.e., before and after the constant-temperature water bath for both maxillary and mandibular denture bases (p<0.05). Conclusion: Denture bases not immersed in the constant-temperature water bath (UBC and LBC groups) exhibited error values within 100 ㎛, whereas those immersed in the water bath (UAC and LAC groups) showed error values exceeding 100 ㎛.

• The Korean Journal of Pharmacology
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• v.13 no.1 s.21
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• pp.7-12
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• 1977

Recently several reports have claimed that the bath temperature changes, such as lower bath temperature, produce supersensitivity on the positive chronotropic effect of catecholamine in cat, mouse and guinea pig atria. However, others showed controversial results against temperature-dependent supersensitivity. Similarly, the inotropic effect of ouabain is diminished in febrile state, however some investigators indicated that cardiac glycoside showed less toxicities and less effects in hypothermic condition. In this study, the effects of norepinephrine and epinephrine on inotropy and chronotropy in isolated rat atria was investigated by changing the temperature of bath ($30^{\circ}C$, $^35{\circ}C$ and $38^{\circ}C$). In addition, the effects of ouabain on atria in hypothermic bath was also studied. The followings are the results. 1. At the lower bath temperature isolated rat atrial rate was decreased and contractility was increased. 2. The chronotropic responses to norepinephrine and epinephrine in $38^{\circ}C$ were decreased when the bath temperature lowered to $35^{\circ}C$ or $30^{\circ}C$, while the inotropic responses were not affected. 3. Hypothermic supersensitivity to norepinephrine or epinephrine was not observed in rat atrium. 4. The inotropic response to ouabain was potentiated but chronotropic response was diminished by a lowering in the bath temperature. In conclusion, the chronotropic response of rat atrium to catecholamine was decreased, however, hypothermic supersensitivity was no longer present in rat atrium and the inotropic response of ouabain was increased at lower bath temperature.

• Physical Therapy Korea
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• v.3 no.2
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• pp.49-54
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• 1996

The purposes of this study were to measure skin temperature and blood flow on the contralateral upper extremity when heat is applied to one upper extremity, were to compare the effect of contrast bath. The subjects were 38 healthy adults with no history of peripheral vascular disease. The subjects of contrast bath were 18 persons and the subjects of warm bath were 20 persons. The subjects of one group were seated with their right arm in water($42^{\circ}C$) up to the mid-forearm. The subjects of the other group were seated with their right arm up to the mid-forearm in water which was changed from warm to cold using the contrast bath technique. The continually changing temperatures and blood flow were measured by an independent observer at intervals of 10, 15, 20, 25 and 30 minutes respectively after the start of the procedure. The results were as follows. The temperature of the warm bath group rose 4.28% over the pre-experimental temperatures and the temperature of the contrast bath group rose 3.41%. There was no statistically significant difference between the two groups. The blood flow of the warm bath group rose 8.31% over the pre-experimental blood flow and the blood flow of the contrast bath group rose 17.24%. There was a statistically significant between the two groups 20 minutes after the start of the procedure. Thus the contrast bath is a more effective method than the warm bath to increase blood flow.

• Corrosion Science and Technology
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• v.13 no.3
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• pp.102-106
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• 2014

Nickel electrodeposition from sulfamate bath has several benefits such as low internal stress, high current density and good ductility. In nickel deposited layers, sulfur induces high temperature embrittlement, as Ni-S compound has a low melting temperature. To overcome high temperature embrittlement problem, adding manganese is one of the good methods. Manganese makes Mn-S compound having a high melting temperature above $1500^{\circ}C$. In this work, the mechanical properties of Ni-Mn deposited layers were investigated by using various process variables such as concentration of Mn$(NH_2SO_3)_2$, current density, and bath temperature. As the Mn content of electrodeposited layers was increased, internal stress and hardness were increased. By increasing current density, internal stress increased, but hardness decreased. With increasing the bath temperature from 55 to $70^{\circ}C$, internal stress of Ni deposit layers decreased, but hardness didn't change by bath temperature. It was likely that eutectoid manganese led to lattice deformation, and the lattice deformation increased hardness and internal stress in Ni-Mn layers. Increasing current density and decreasing bath temperature would increase a mount of $H_2$ absorption, which was a cause for the rise of internal stress.

• Journal of Korean Biological Nursing Science
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• v.19 no.3
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• pp.151-157
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• 2017

Purpose: The purpose of this study was to identify the effects of hand and foot baths on sleep and body temperature of the elderly. Methods: The research was designed for a nonequivalent control group before and after the test design. The subjects of this study totaled 43, aged 65 and over (23 people in hand bath group and 20 people in a foot bath group), who received a written voluntary consent to participate in experimental treatment and are in the W care center, S Nursing Home, and H care center in Seoul. Data were collected with questionnaires and observations, and were analyzed on the basis of frequency, percentage, mean, standard deviation, ${\chi}^2-test$, Fisher exact test, t-test and paired t-test. Results: There are no significant differences in homogeneity test of a dependent variable between groups (hand bath, foot bath). The differences between 2 groups on the sleep quality score and systolic blood pressure, diastolic blood pressure temperature were not significant statistically except on the pulse. Conclusion: Based on the results of this study, hand bath is as efficient as foot bath. Therefore, a hand bath can be a nursing intervention in order to enrich sleep quality for the elderly because a hand bath is more convenient than foot bath.

• Journal of the Korean Society of Clothing and Textiles
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• v.12 no.2 s.27
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• pp.133-144
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• 1988

Silk fabrics were degummed and dyed in one bath under the condition of high temperature and high pressure and the results obtained were summerized as follows. 1. The degumming ratio is nearly the same as that of two bath method under the normal condition and the optimal condition is for 30 minutes at $120^{\circ}C$. 2. The dyeing absorption ratio is a little lower than that of two bath method. 3. The tensile strength and elongation are hardly shown the difference between two methods. 4. The fastness of the dyed fabric of one bath method is a little better than that of two bath method. (light, washing, rubbing) 5. The stiffness of the silk fabric treated by one bath method is a little harshier compare to that of two bath method.

• Journal of the Korea Safety Management & Science
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• v.19 no.4
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• pp.35-42
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• 2017

A number of plating companies have been exposed to the risk of fire due to unexpected temperature increasing of water or other reasons in a plating bath. Since the companies are not able to forecast the unexpected temperature increasing of plating bath and most of raw materials in the bath have low ignition temperature, it is easy to be exposed to the risk of fire. Thus, in previous study, we tried to monitor and notice the dangerous change of temperature of water immediately to prevent the risk of fire from plating process. However, unfortunately previous studies were not able to shut out the fundamental cause of fire since bath temperature sensor can detect air temperature when the level sensor was malfunctioned. In this paper we developed the Teflon heater which contains a built in temperature sensor and improved plating equipment system. Teflon heater is improved using Pt $100{\Omega}$ sensor which can detect until $600^{\circ}C$. When the bath temperature sensor detects over $60^{\circ}C$ or the Teflon heater sensor detects over $240^{\circ}C$ they temporarily shut down the heater to control temperature. Also relay completely shuts down main power when detects instant temperature is detected over 5% of $240^{\circ}C$ by the heater sensor to prevent teflon melting down and fire spreads. Developed plating equipment system can monitor a real time temperature in the teflon tube and bath water. Therefore we think the proposed plating equipment can eliminate the possibility of fire in plating processes fundamentally.

• Journal of Korea Multimedia Society
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• v.22 no.2
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• pp.242-249
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• 2019

Old people and patients with cardiovascular disease could die of a heart attack in the bath with heated water for a long time. Various researches have been studied to prevent these accidents from happening such as measuring the ECG signal when taking bath. However, these devices are hard to use and the higher price is not easily accepted by the public. In this paper, a low-cost and use-friendly, real time high precision water temperature monitoring device to prevent heart attack in the bath was developed. The device with waterproof design that lets the device can float on the surface of the water, and an accurate way to make water temperature measurement method was proposed by this paper that is immerging the sensor into water with 4cm depth to measure the temperature of underwater. The manufactured device was conducted to two experiments; one was to verify the basic functions of the device, and another one was for compare the proposed device with commercial products for monitoring the water temperature in the bathtub. As the experimental results shown, the proposed device has stable performance for the water temperature measurement and communicating with laptop in wireless.

• Korean Journal of Materials Research
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• v.32 no.9
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• pp.361-368
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• 2022

The overall process, from the pre-treatment of aluminum substrates to the eco-friendly neutral electroless Ni-P plating process, was observed, compared, and analysed. To remove the surface oxide layer on the aluminum substrate and aid Ni-P plating, a zincation process was carried out. After the second zincation treatment, it was confirmed that a mostly uniform Zn layer was formed and the surface oxide of aluminum was also removed. The Ni-P electroless plating films were formed on the secondary zincated aluminum substrate using electroless plating solutions of pH 4.5 and neutral pH 7.0, respectively, while changing the plating bath temperature. When a neutral pH7.0 electroless solution was used, the Ni-P plating layer was uniformly formed even at the plating bath temperature of 50 ℃, and the plating speed was remarkably increased as the bath temperature was increased. On the other hand, when a pH 4.5 Ni-P electroless solution was used, a Ni-P plating film was not formed at a plating bath temperature of 50 ℃, and the plating speed was very slow compared to pH 7.0, although plating speed increased with increasing bath temperature. In the P contents, the P concentration of the neutral pH 7.0 Ni-P electroless plating layer was reduced by ~ 42.3 % compared to pH 4.5. Structurally, all of the Ni-P electroless plating layers formed in the pH 4.5 solution and the neutral (pH 7.0) solution had an amorphous crystal structure, as a Ni-P compound, regardless of the plating bath temperature.

• Corrosion Science and Technology
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• v.9 no.5
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• pp.175-186
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• 2010

The auto industry is demanding more ductile high-strength steel grades to build lighter and stronger car bodies. The hot-dip galvanizing problems of these new steel grades are creating a demand for an improved method to control zinc wettability. The simplest way to improve zinc wettability on industrial hot-dip galvanizing lines is to increase the strip immersion temperature at zinc bath entry for enhancing the aluminothermic reaction. However, this practice increases the reactivity due to overheating the zinc in the snout which induces the formation of brittle Fe-Zn compounds at the strip/coating interface with the formation of higher amounts of dross in the zinc bath and snout contamination. Thus, this simple practice can only be utilized for short production periods of one to two hours without deteriorating coating quality. This problem has been solved by employing a technique that allows the use of a higher and attuned strip immersion temperature at zinc bath entry while still maintaining a constantly low zinc bath temperature. This has been proven to provide the solution for both the improved wettability and a significant reduction in the amounts of dross in the zinc bath.