• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.768-772
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• 2013

Layered mixed metal hydroxy double salts (HDS) with the formulas $(Cu_{0.75}Ni_{0.25})_2(OH)_3NO_3$ ((Cu, Ni)-HDS) and $Cu_2(OH)_3NO_3$ ((Cu, Cu)-HDS) were prepared via slow hydrolysis reactions of CuO with $Ni(NO_3)_2$ and $Cu(NO_3)_2$, respectively. The crystal structures, morphologies, bonding natures, and magnetic properties of (Cu, Ni)-HDS and (Cu, Cu)-HDS were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transformation infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and a superconducting quantum interference device (SQUID). Even though (Cu, Ni)-HDS has a similar layered structure to that of (Cu, Cu)-HDS, the bonding nature of (Cu, Ni)-HDS is slightly different from that of (Cu, Cu)-HDS. Therefore, the magnetic properties of (Cu, Ni)-HDS are significantly different from those of (Cu, Cu)-HDS. The origin of the abnormal magnetic properties of (Cu, Ni)-HDS can be explained in terms of the bonding natures of the interlayer and intralayer structures.

• Journal of Korean Neurosurgical Society
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• v.46 no.4
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• pp.351-354
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• 2009

Objective : Combined hyperative dysfunction syndrome (HDS) defined as the combination of HDSs such as trigeminal neuralgia (TN). hemifacial spasm (HFS) and glossopharyngeal neuralgia (GPN), which mayor may not occur simultaneously on one or both sides. We reviewed patients with combined HDS and demonstrated their demographic characteristics by comparing them with those of patients with a single HDS. Methods : Between October 1994 and February 2006, we retrospectively studied a series of 1,720 patients who suffered from HDS and found 51 patients with combined HDSs. We analyzed several independent variables in order to evaluate the prevalence and etiologic factors of combined HDS. Results : The combined HDS group accounted for 51 of 1,720 (2.97%) patients with HDS; 27 cases of bilateral HFS, 10 cases of bilateral TN and 14 cases of HFS with TN. Their mean age was 52.1 years (range, 26-79 years). There were 5 men and 46 women. Seven patients had synchronous and 44 patients metachronous onset of HDSs. By comparison of combined and single HDS groups, we found that age and hypertension were closely associated with the prevalence of combined HDS (p<0.05). Conclusion : This study revealed that combined HDS was very rare. Hypertension and age might be the most important causative factors to evoke combined HDS.

• Journal of Environmental Health Sciences
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• v.45 no.4
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• pp.381-393
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• 2019

Objectives: The purpose of this study was to assess the association between the use of humidifier disinfectant (HD) and bronchiolitis and allergic rhinitis diagnoses in Korean children. Methods: This study used data from the $8^{th}$ panel study on Korean children in 2015. Of these 2150 cases, 1598 cases were used for the final study. Diagnoses of bronchiolitis and allergic rhinitis by medical doctors were self-reported as outcome variables. Whether children had used HDs or not, the periods of using HDs were used as independent variables. Results: A total of 77.0% had used a humidifier, and the rate of HD usage among humidifier users was found to be 35.4%. When comparing 'children who had used HDs for less than 12 months' and 'children who had used HDs for more than 12 months' with 'children who had not used HDs', the adjusted odds ratio (OR)s for 'bronchiolitis' were 1.38 (95% confidence interval (CI), 1.36-1.40) and 1.80 (95% CI, 1.71-1.89), respectively. When comparing 'children who had used HDs for less than 12 months' and 'children who had used HDs for more than 12 months' with 'children who had not used HDs', the adjusted ORs for 'allergic rhinitis' were 1.44 (95% CI, 1.42-1.46) and 1.43 (95% CI, 1.37-1.49), respectively. Conclusions: The period of using HDs was statistically significantly associated with increased odds of bronchiolitis and allergic rhinitis. The results of this study will provide a very useful scientific basis for establishing the environmental health policy and using the educational data related to the use of humidifier disinfectant in the future.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.8
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• pp.1276-1290
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• 1997

The previous elastic stiffness formulas of leaf type holddown spring assemblies(HDSs) have been corrected and extended to be able to consider the point of taper runout for the TT-HDS and all the strain energies for both the TT-HDS and the TW-HDS based on Euler beam theory and Castigliano'stheorem. The elastic stiffness sensitivity of the leaf type holddown spring assemblies was analyzed using the derived elastic stiffness formulas and their gradient vectors obtained from the mid-point formula. As a result of the sensitivity analysis, the elastic stiffness sensitivity at each design variable is quantified and design variables having remarkable sensitivity are identified. Among the design variables, leaf thickness is identified as that of having the most remarkable sensitivity of the elastic stiffness. In addition, it was found that the sensitivity of the leaf type HDS's elastic stiffness is exponentially correlated to the leaf thickness.

• ETRI Journal
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• v.7 no.2
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• pp.43-48
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• 1985

일반적으로 시분할 전자 교환기의 time-switch로는 RAM을 이용한 방식이 많이 사용되고 있는데 본고에서는 간단한 하드웨어와 빠른 교환 속도의 특징을 갖는 고속 디지틀 스위칭 IC, HDS(Highspeed Digital Switch)-LSI에 관하여 간단히 소개하고자 한다. 먼저 일반적인 time-switch의 구조와 동작에 대해 간단히 설명하고 HDS-LSI의 기본 원리와 구조 그리고 응용 분야에 대해 예를들어 설명하였다.

• Nuclear Engineering and Technology
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• v.30 no.4
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• pp.287-297
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• 1998

The elastic stiffness formula of leaf type holddown spring(HDS) assembly is verified by comparing the values of elastic stiffness with the characteristic test results of the HDS's specimens. The comparisons show that the derived elastic stiffness formula is useful in reliably estimating the elastic stiffness of leaf type HDS assembly. The elastic stiffness sensitivity of leaf type HDS assembly is analyzed using the formula and its gradient vectors obtained from the mid-point formula. As a result of sensitivity analysis, the elastic stiffness sensitivity with respect to each design variable is quantified and design variables of large sensitivity are identified. Among the design variables, leaf thickness is identified as the most sensitive design variable to the elastic stiffness of leaf type HDS assembly. In addition, the elastic stiffness sensitivity, with respect to design variable, is in power-law type correlation to the base thickness of the leaf.

• Journal of Environmental Health Sciences
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• v.45 no.3
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• pp.273-284
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• 2019

Objective: This study was performed to estimate the number of those who used humidifier disinfectants (HDs) and experienced health effects from exposure to HDs in Korea between 1994 and 2011. Methods: A nationwide interview survey was conducted for the representative sample to identify the proportion of those who used HDs among the general population (n=3,001). Another online survey was conducted for those exposed to HDs to find the proportion of those who experienced health effects among those who were exposed to HDs (n=3,993). Statistics for population size by region and year (1994-2011) were used to estimate the cumulative number of those exposed to HDs and those who experienced health effects. In terms of the proportion of those exposed to HDs, those less than 30 years of age were excluded due to an issue related to information bias. Various approaches for estimation included the capture-recapture method for estimation of those who experienced health effects. Results: The cumulative proportion of those exposed to HDs was 6.7% among the general population, and the proportion of those who experienced health effects among those who were exposed to HDs was 13.9%. Based on these factors, it was estimated that 3.5 to 4.0 million people were exposed to HDs and 350 to 400 thousand experienced health effects at least requiring visiting a hospital. Conclusion: It is suggested that a nationwide representative sample may be essential for population size estimation of those exposed to environmental risk factors and of those who experienced health effects.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.1
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• pp.31-46
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• 2006

Purpose : The Purpose of this research was to investigate the effects of antithromb otic activities of Honghwadangguisan(HDS) Methods : Measured the effect which was given to blood flow rate through the regular volume of glass tube after the blood was diluted five times with ACD soulution. Antithrombotic effect was calculated as a percentage of the experimental animal figure protected from the paralysis of hind legs or death of the mouse that is caused from the administration of platelet aggregation regent. Each of the groups consisted in 8 mice, was divided into Normal, Control, and HBS. All of these 3 group were supplied a saline solution and after an hour the control group brought the dextran extravasated blood. Also the HDS group was dosed to the experimental mice with Oral Zonde one day before the experiment. After that, the mice were abstained from food. And then we gave a measured amount of it before an hour. Finally, it gave rise to dextran extravasated blood as well as the Control group. Results : The results were obtained as follows. In vitro, HDS inhibited platelet aggregation induced by ADP and epinephrine significantly as compared with the control group. HDS showed fibrinolytic activity insignificantly as compared with the control group. HDS reduced blood flow rate in significantly as compared with the control group. In vivo HDS inhibited pulmonary embolism induced by collagen and epinephrine (inhibitive rate 50%). HDS increased number of platelet, fibrinogen amount and shortened prothrombin time, activated partial thromboplastin time significantly but reduced blood flow rate insignificantly as compared with the control group in thrombus model induced by dextran. Conclusion : HDS is effective antithrombotic activity from experimental result.

• The Transactions of the Korea Information Processing Society
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• v.5 no.10
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• pp.2521-2532
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• 1998

This paper proposes Heterogeneous Duplicatio Scheduling(HDS) which alleviates excessive communication overhead between tasks for distributed computing on a teerogeneous distributed environment. HDS is to allocate a copy of a task that causes excesive data communication with a message receiving task to the dame machine wherein the message receiving task is scheduled. The proposed algorithm allows only the duplication of parent tasks so as not to increase the complexity of the algorithm. Simulation on various type of task graphs provides that the scheduling results by using HDS are better than those by using the existing geterogencous cheduling schemes.

• Journal of Environmental Health Sciences
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• v.46 no.4
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• pp.457-469
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• 2020

Objective: This study was designed to estimate the precise nationwide number of those who used humidifier disinfectants (HDs) and experienced specific health effects, including death, due to exposure to HDs in Korea between 1994 and 2011. Methods: A total of 5,000 households (15,472 people) were surveyed by stratifying the sample with a design that is equivalent to nationally approved household systematic sampling and face-to-face interviews from October 16, 2019 to December 30, 2019. Results: The proportion of use of humidifier disinfectants at home was 18.4% (2,844/15,472 people) and the proportion of those who experienced health effects among those who were exposed to HDs was 10.7% (303/2,844 people). Based on these factors, it was estimated that 8.94 million people (95% CI=8.25-9.63 million) were exposed to HDs and 0.95 million people (95% CI=0.87-1.02 million) experienced health effects, which means almost one in five and one in fifty Koreans respectively. The estimated number of deaths from HDs were 20,366 people (95% CI=18,801-21,931). Conclusion: The survey was large and analyzed a representative sample across the country, so this estimation of the nationwide population exposed and at risk to HDs is more accurate and reliable than previous studies. However, it is necessary to confirm whether results similar to those of this study can be reproduced through a survey using a cross-sectional survey at the national level. In particular, a survey focused on death cases is needed.