• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.5 no.2
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• pp.147-159
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• 1995

This study was conducted to introduce fundamental data of hand-arm vibration and noise exposure levels with impact wrenches(double-hammer impact wrenches and oil-pulse impact wrenches) used in automobile assembly lines considering the process variables and tool variables. In studing, products per day, required time screwing the bolts or nuts per bolts or nut were considered as process variables, and capacity of bolts or nuts, air consumptions per minute, tool weights, RPM were considered as tool variables. Hand-arm vibration levels of 3 axis in each hand were measured using the instruments compling with ISO/DIS 5349 and noise levels were measured using a noise logging dosimeter. The results were as follows : 1. Required time to screwing the bolt or nut by oil-pulse impact wrenches is shorter than double-hammer impact wrenches but total daily exposure time of oil-pulse impact wrenches was higher than double-hammer impact wrenches because the number of bolts or nuts per cycle was many. 2. Oil-pulse impact wrenches have been used to screwing the large bolt or nut in comparing with double-hammer impact wrenches and required time to screwing the bolts or nuts were shorter than double-hammer impact wrenches because oil-pulse impact wrenches were using high RPM and large air consumption per minute. Noise level of oil-pulse impact wrenches was 8 dB(A) lower than double-hammer impact wrenches. 3. Dominant hand-arm vibration levels of double-hammer impact wrenches in each hand were $8.24m/sec^2$ of Zh axis in right hand and $9.60m/sec^2$ of Xh axis in left hand. Dominant hand-arm vibration level of oil-pulse impact wrenches in each hand was $2.59m/sec^2$ of Xh axis in right hand and $3.23m/sec^2$ of Yh axis in left hand. 4. In double-hammer impact wrenches, corresponding hand-arm vibration levels of Xh, Yh, Zh axis in left hand were higher than hand-arm vibration levels of right hand in 3 axis. In oil-pulse impact wrenches, Xh axis of right, Yh axis of left, Zh axis of left were higher than the corresponding hand-arm vibration levels of Xh, Yh, Zh axis in right and left hand. 5. Correlation coefficients among Xh, Yh. Zh axis of right and left hand hand-arm vibration levels in double-hammer impact wrenches and oil-pulse impact wrenches were commonly high in Yh axis and correlation coefficients of Yh axis in double-hammer impact wrenches and oil-pulse impact wrenches were 0.76 and 0.86,respectively. 6. As a measure repetitiveness, plotting total daily exposure time with the number of bolts or nut per cycle, direct correlation was shown between repetitiveness and hand-arn vibration exposure, and correlation coefficient between the number of bolts or nut per cycle and total daily exposure time in double-hammer impact wrenches, oil-pulse impact wrenches were 0.84 and 0.50, respectively. 7. Considering the total acceleration level and tool variables in double-hammer impact wrenches and oil-pulse impact wrenches, air consumption in right hand, and bolt or nut capacity in left hand were commonly the variable that explainability was high. Considering the noise and tool variables in double-hammer impact wrenches and oil-pulse impact wrenches, air consumption per minute was commonly the variable that explainability was high.

• Journal of Technology Innovation
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• v.26 no.3
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• pp.37-68
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• 2018

Since the 20th century, automobiles, which are the most common means of transportation, have been evolving as the use of electronic control devices and automotive semiconductors increases dramatically. Automotive semiconductors are a key component in automotive electronic control devices and are used to provide stability, efficiency of fuel use, and stability of operation to consumers. For example, automotive semiconductors include engines control, technologies for managing electric motors, transmission control units, hybrid vehicle control, start/stop systems, electronic motor control, automotive radar and LIDAR, smart head lamps, head-up displays, lane keeping systems. As such, semiconductors are being applied to almost all electronic control devices that make up an automobile, and they are creating more effects than simply combining mechanical devices. Since automotive semiconductors have a high data rate basically, a microprocessor unit is being used instead of a micro control unit. For example, semiconductors based on ARM processors are being used in telematics, audio/video multi-medias and navigation. Automotive semiconductors require characteristics such as high reliability, durability and long-term supply, considering the period of use of the automobile for more than 10 years. The reliability of automotive semiconductors is directly linked to the safety of automobiles. The semiconductor industry uses JEDEC and AEC standards to evaluate the reliability of automotive semiconductors. In addition, the life expectancy of the product is estimated at the early stage of development and at the early stage of mass production by using the reliability test method and results that are presented as standard in the automobile industry. However, there are limitations in predicting the failure rate caused by various parameters such as customer's various conditions of use and usage time. To overcome these limitations, much research has been done in academia and industry. Among them, researches using data mining techniques have been carried out in many semiconductor fields, but application and research on automotive semiconductors have not yet been studied. In this regard, this study investigates the relationship between data generated during semiconductor assembly and package test process by using data mining technique, and uses data mining technique suitable for predicting potential failure rate using customer bad data.

• Journal of Korea Water Resources Association
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• v.50 no.7
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• pp.455-465
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• 2017

Understanding of the two-dimensional velocity field is crucial in terms of analyzing various hydrodynamic and fluvial processes in the riverine environments. Until recently, many numerical models have played major roles of providing such velocity field instead of in-situ flow measurements, because there were limitations in instruments and methodologies suitable for efficiently measuring in the broad range of river reaches. In the last decades, however, the advent of modernized instrumentations started to revolutionize the flow measurements. Among others, acoustic Doppler current profilers (ADCPs) became very promising especially for accurately assessing streamflow discharge, and they are also able to provide the detailed velocity field very efficiently. Thus it became possible to capture the velocity field only with field observations. Since most of ADCPs measurements have been mostly conducted in the cross-sectional lines despite their capabilities, it is still required to apply appropriate interpolation methods to obtain dense velocity field as likely as results from numerical simulations. However, anisotropic nature of the meandering river channel could have brought in the difficulties for applying simple spatial interpolation methods for handling dynamic flow velocity vector, since the flow direction continuously changes over the curvature of the channel shape. Without considering anisotropic characteristics in terms of the meandering, therefore, conventional interpolation methods such as IDW and Kriging possibly lead to erroneous results, when they dealt with velocity vectors in the meandering channel. Based on the consecutive ADCP cross-sectional measurements in the meandering river channel. For this purpose, the geographic coordinate with the measured ADCP velocity was converted from the conventional Cartesian coordinate (x, y) to a curvilinear coordinate (s, n). The results from application of A-VIM showed significant improvement in accuracy as much as 41.5% in RMSE.

• Geophysics and Geophysical Exploration
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• v.13 no.3
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• pp.268-276
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• 2010

Earthquake Hazard Mitigation Law was activated into force on March 2009. By the law, the obligation to monitor the effect of earthquake on the facilities was extended to many organizations such as gas company and local governments. Based on the estimation of National Emergency Management Agency (NEMA), the number of free-surface acceleration stations would be expanded to more than 400. The advent of internet protocol and the more simplified operation have allowed the quick and easy installation of seismic stations. In addition, the dynamic range of seismic instruments has been continuously improved enough to evaluate damage intensity and to alert alarm directly for earthquake hazard mitigation. For direct visualization of damage intensity and area, Real Time Intensity COlor Mapping (RTICOM) is explained in detail. RTICOM would be used to retrieve the essential information for damage evaluation, Peak Ground Acceleration (PGA). Destructive earthquake damage is usually due to surface waves which just follow S wave. The peak amplitude of surface wave would be pre-estimated from the amplitude and frequency content of first arrival P wave. Earthquake Early Warning (EEW) system is conventionally defined to estimate local magnitude from P wave. The status of EEW is reviewed and the application of EEW to Odesan earthquake is exampled with ShakeMap in order to make clear its appearance. In the sense of rapidity, the earthquake announcement of Korea Meteorological Agency (KMA) might be dramatically improved by the adaption of EEW. In order to realize hazard mitigation, EEW should be applied to the local crucial facilities such as nuclear power plants and fragile semi-conduct plant. The distributed EEW is introduced with the application example of Uljin earthquake. Not only Nation-wide but also locally distributed EEW applications, all relevant information is needed to be shared in real time. The plan of extension of Korea Integrated Seismic System (KISS) is briefly explained in order to future cooperation of data sharing and utilization.

• Geophysics and Geophysical Exploration
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• v.14 no.1
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• pp.80-87
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• 2011

Autonomous underwater vehicles (AUVs) present the important advantage of being able to approach the seafloor more closely than surface vessel surveys can. To collect bathymetric data, bottom material information, and sub-surface images, multibeam echosounder, sidescan sonar (SSS) and subbottom profiler (SBP) equipment mounted on an AUV are powerful tools. The 3000m class AUV URASHIMA was developed by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC). After finishing the engineering development and examination phase of a fuel-cell system used for the vehicle's power supply system, a renovated lithium-ion battery power system was installed in URASHIMA. The AUV was redeployed from its prior engineering tasks to scientific use. Various scientific instruments were loaded on the vehicle, and experimental dives for science-oriented missions conducted from 2006. During the experimental cruise of 2007, high-resolution acoustic images were obtained by SSS and SBP on the URASHIMA around the northern Kumano Basin off Japan's Kii Peninsula. The map of backscatter intensity data revealed many debris objects, and SBP images revealed the subsurface structure around the north-eastern end of our study area. These features suggest a structure related to the formation of the latest submarine fan. However, a strong reflection layer exists below ~20 ms below the seafloor in the south-western area, which we interpret as a denudation feature, now covered with younger surface sediments. We continue to improve the vehicle's performance, and expect that many fruitful results will be obtained using URASHIMA.

• Journal of Korean Academy of Nursing Administration
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• v.2 no.2
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• pp.97-107
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• 1996

Nursing standards determine the type and extent of services that are delivered to the patients and define quality care and communicate the institution's expectations of care. Thus, taking the standard of care and incorporating it into a welldefined indicator of excellent patient care becomes one of the first activities in setting up the nursing service's quality assurance process. The purpose of this study was to determine the impact of using a nursing care standards for the quality of nursing care in gastrectomy patients. The subjects were composed of fourty-two under going gastrectomy patients with stomach cancer in general surgery nursing care unit of K University Hospital in Pusan. The data was collected from January 3 to April 13,1996. The subjects were divided into a control group - those admitted from Jan.3 to Feb.12 and an experimental group those admitted from Feb.18 to April 13. The instruments used for this study were a nursing care standards in gastrectomy patients developed by the investigator and an evaluation tool for the quality of nursing care in abdominal surgery patients developed by Byoung-Sook Lee in 1995. The data was analized by means of chi-square test, t-test and Cronbach-alpha test with the SAS System. The result was as follows : The hypothesis, that scores of the quality of nursing care in the experimental group would be higher than that of the control group. was supported(t=-6.12, p=0.00). The detailed results of each standards of evaluation tool were as follows : The mean score of the experimental group was significantly higher than that of the control group in audit standard 1:'Collection of basic data of the patients', (t=-3.76, p=0.00). The mean score of the experimental group was significantly higher than that of the control group in audit standard 2 : 'Defining nursing diagnoses(or nursing problems)', (t= (-), p= (-) ). The mean score of the experimental group was significantly higher than that of the control group in audit standard 3:'Estabilishment of nursing care plan according to nursing diagnoses(or nursing problems)',(t= (-), p= (-) ). The mean score of the experimental group was significantly higher than that of the control group in audit stndard 4:'Implimentation of nursing care plan', (t=-2.38, p=0.01). The mean score of the experimental group was significantly higher than that of the control group in audit standard 8 : 'Increase of the knowledge of health related to surgery',(t=-2.40, p=0.01). No significant differences between the mean scores of the experimental group and that of the control group in audit standard 5 : 'Recover and maintain of the physical function', audit standard 6:'Prevention of the post-operative complication', audit standard 7 : 'Decrease of discomfort caused by operation', and audit standard 9 : 'Patient satisfaction in nursing care' were found. The standards of evaluation tool were devided into two dimension. One was process dimension which contains four standards(audit standard 1 to 4), the other was outcome dimension which contains five standards(audit standard 5 to 9). The mean score of the experimental group was significantly higher than that of the control group in process dimension (t=-12.30, p=0.00), but no significant difference between the mean scores of the experimental group and that of the control group in outcome dimension was found. From these results, it is concluded that using a nursing care standards in gastrectomy patients promotes quality of nursing care and nursing care standards of various fields are necessary for effective nursing care.

• Journal of Music and Human Behavior
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• v.4 no.2
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• pp.1-17
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• 2007

Huge growth in developmental level, new accomplishment, and The period of adolescents is not only the transition stage but also improvement of academic level. In this level of stage, adolescents have difficulties in development, so they show psychological abnormality such as stress and depression. They could develop mental disorder such as depression or anxiety if they do not overcome the abnormality. According to the situation of the insufficiency of the decent program for adolescents' mental health in the current society, we are strongly requested to develop the psycho-therapeutic program for them. Therefore, in this study, we examined the effect of the musical activities as blues music structure on the improvement of the Self-Efficacy in the female middle school students who have depressive tendencies as well as what they experienced through the activities. The 3 participants were selected out of 70 students in the first year at the "D" middle school in Seoul by being tested with Child Depression Inventory(CDI) and Self-Efficacy Scale(SES). The musical activities were built with 3 steps. Of which, the first one was the introduction to each other, the formation of rapport, and induction of their interests to the musical activities through blues. The second one was letting participants learn the blues music structure by practice and play assigned music(including improvisation) during later 5 sessions with different difficulties at each session. The third one was giving them opportunities to play a music out of the acquired ones during the session or creative music by their own, which results in maximizing musical activities and an acquired experience. As a result, first of all, the scores of CDI test of 3 participants in 10 time sessions showed slight changes, suggesting the negative correlation between CDI and SES even though changes were not big differences. Secondly, the scores of SES test of 3 subjects in 10 time sessions were all changed and especially preference for tasking was significant. Thirdly, the scores of SES for musical playing test of 3 participants in 10 time sessions were all changed and especially preference for musical tasking was significant shown. Finally, according to answers of 3 participants in 10 time sessions for the after questionnaire on musical activities, participants experienced affirmative self-confidence and positive emotion. Taken together, it was suggested that musical activities using blues music structure could be promising therapeutic intervention method.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.49
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• pp.283-324
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• 2011

The purpose of this paper is to research the air waybill and the carrier's liability in respect of the carriage of cargo by air under the Montreal Convention of 1999. The Warsaw Convention for the unification of certain rules for international carriage by air was adopted in 1929 and modified successively in 1955, 1961, 1971, 1975 and 1999. The Montreal Convention of 1999 modernized and consolidated the Warsaw Convention and related instruments. Under the Montreal Convention, in respect of the carriage of cargo, the air waybill shall be made out by the consignor. If, at the request of the consignor, the carrier makes it out, the carrier shall be deemed to have done so on behalf of the consignor. The air waybill shall be made out in three orignal parts. Under the Montreal Convention, the consignor shall indemnify the carrier against all damages suffered by the carrier or any other person to whom the carrier is liable, by reason of the irregularity, incorrectness or incompleteness of the particulars and statement furnished by the consignor or on its behalf. The air waybill is not a document of title or negotiable instrument. Under the Montreal Convention, the air waybill is prima facie evidence of the conclusion of the contract, of the acceptance of the cargo and of the conditions of carriage. If the carrier carries out the instructions of the consignor for the disposition of the cargo without requiring the production of the part of the air waybill, the carrier will be liable, for any damage which may be accused thereby to any person who is lawfully in possession of the part of the air waybill. Under the Montreal Convention, the carrier is liable by application of principle of strict liability for the damage sustained during the carriage of cargo by air. The carrier is liable for the destruction or loss of, or damage to cargo and delay during the carriage by air. The period of the carriage by air does not extend to any carriage by land, by sea or by inland waterway performed outside an airport. Under the Montreal Convention, the carrier's liability is limited to a sum of 17 Special Drawing Rights per kilogramme. Any provision tending to relieve the carrier of liability or to fix a lower limit than that which is laid down in this Convention shall be and void. Under the Montreal Convention, if the carrier proves that the damage was caused by the negligence or other wrongful act or omission of the person claiming compensation, or the person from whom he derives his rights, the carrier shall be wholly or partly exonerated from ist liability to the claimant to the extent that such negligence or wrongful act or omission caused the damage. Under the Montreal Convention, any action for damages, however founded, whether under this Convention or in contract or in tort or otherwise, can only be brought subject to the conditions and such limits of liability as are set out in this Convention. Under the Montreal Convention, in the case of damage the person entitled to delivery must complain to the carrier forthwith after the discovery of the damage, and at the latest, within fourteen days from the date of receipt of cargo. In the case of delay, the complaint must be made at the latest within twenty-one days from the date on which the cargo has been placed at his disposal. if no complaint is made within the times aforesaid, no action shall lie against the carrier, save in the case of fraud on its part. Under the Montreal Convention, the right to damage shall be extinguished if an action is not brought within a period of two years, reckoned from the date of arrival at the destination, or from the date on which the aircraft ought to have arrived, or from the date on which the carriage stopped. In conclusion, the Montreal Convention has main outstanding issues with respect to the carrier's liability in respect of the carriage of cargo by air as follows : The amounts of limits of the carrier's liability, the duration of the carrier's liability, and the aviation liability insurance. Therefore, the conditions and limits of the carrier's liability under the Montreal Convention should be readjusted and regulated in detail.

• Korean Journal of Remote Sensing
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• v.30 no.4
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• pp.455-464
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• 2014

After launching the Geostationary Ocean Color Imager (GOCI) on June 2010, field campaigns were performed routinely around Korean peninsula to collect in-situ data for calibration and validation. Key measurements in the campaigns are radiometric ones with field radiometers such as Analytical Spectral Devices FieldSpec3 or TriOS RAMSES. The field radiometers must be regularly calibrated. We, in the paper, introduce the optical laboratory built in KOSC and the relative calibration method for in-situ measurement spectroradiometer. The laboratory is equipped with a 20-inch integrating sphere (USS-2000S, LabSphere) in 98% uniformity, a reference spectrometer (MCPD9800, Photal) covering wavelengths from 360 nm to 1100 nm with 1.6 nm spectral resolution, and an optical table ($3600{\times}1500{\times}800mm^3$) having a flatness of ${\pm}0.1mm$. Under constant temperature and humidity maintainance in the room, the reference spectrometer and the in-situ measurement instrument are checked with the same light source in the same distance. From the test of FieldSpec3, we figured out a slight difference among in-situ instruments in blue band range, and also confirmed the sensor spectral performance was changed about 4.41% during 1 year. These results show that the regular calibrations are needed to maintain the field measurement accuracy and thus GOCI data reliability.

• Journal of Sericultural and Entomological Science
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• v.16 no.2
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• pp.77-98
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• 1974

This study was carried out ill an attempt to investigate the properties and activities of sericin obtained from silk cocoon shells in silk reeling water through various instrumental analyses. In addition, the effects of the characteristics in sericin solubility on the reeling process and silk qualities were also studied on the basis of tile above conditions. The results obtained are as follows： I. The sericin properties and activities through various analytical instruments. 1. The water solubility of each amino acid such as serine, glycine. glutamic and aspartic acids against the pH modified water by using automatic amino acid analyzer, showed the lowest solubility at PH 5, but it increased according to drifting toward the alkalinity. 2. When the obtained sericin particles by water pH variation were observed with the electronic microscope, it was found for the sericin Particles to expand in the alkaline regions. 3. The IR spectrum results showed the differences among the pH modified sericin solutions at the range of 2,100cm-1 and 1.890cm-1 of wave number. 4. The existence of sericin with in silk fabrics made differences in the X-ray interference intencity, that is, the non-degummed fabrics had the interference peak at 2$\theta$=14$^{\circ}$, 17$^{\circ}$, 24$^{\circ}$, and the degummed ones had it at 2$\theta$=17$^{\circ}$, 18$^{\circ}$, 20$^{\circ}$, 23$^{\circ}$, 26$^{\circ}$. II. The results of sericin solubility for silk reeling process. 1. The sericin solubility and swelling had a tendency to increase up with high M-alkalinity and pH value of water. But in case of acidity. water hardness and concentration of ethylene glycol were high, the sericin solubility and swelling were decreased. 2. With the filature experiments, the best conditions of filature orator are summarized as fellows ; a. pH; 6.9${\pm}$0.2 d. acidity; below10ppm b. total hardness; 55：5ppm e. Fe ion; none c. M-alkalinity; 40${\pm}$10ppm