• Journal of the Korean Data and Information Science Society
• /
• v.21 no.6
• /
• pp.1289-1303
• /
• 2010

The need for statistical process control to check the performance of a process is becoming more important in chemical and pharmaceutical industries. This study illustrates the method to determine whether a process is in control and how to produce and interpret control charts. In the experiment, a stream of green dyed water and a stream of pure water were continuously mixed in the process. The concentration of the dye solution was measured before and after the mixer via a spectrophotometer. The in-line mixer provided benefits to the dye and water mixture but not for the stock dye solution. The control charts were analyzed, and the pre-mixer process was in control for both the stock and mixed solutions. The R and X-bar charts showed virtually all of the points within control limits, and there were no patterns in the X-bar charts to suggest nonrandom data. However, the post-mixer process was shown to be out of control. While the R charts showed variability within the control limits, the X-bar charts were out of control and showed a steady increase in values, suggesting that the data was nonrandom. This steady increase in dye concentration was due to discontinuous, non-steady state flow. To improve the experiment in the future, a mixer could be inserted into the stock dye tank. The mixer would ensure that the dye concentration of the stock solution is more uniform prior to entering the pre-mixer ow cell. Overall, this would create a better standard to judge the water and dye mixture data against as well.

• International Journal of Concrete Structures and Materials
• /
• v.11 no.1
• /
• pp.135-149
• /
• 2017

The prediction of the actual ultimate capacity of confined concrete columns requires partial confinement utilization under eccentric loading. This is attributed to the reduction in compression zone compared to columns under pure axial compression. Modern codes and standards are introducing the need to perform extreme event analysis under static loads. There has been a number of studies that focused on the analysis and testing of concentric columns. On the other hand, the augmentation of compressive strength due to partial confinement has not been treated before. The higher eccentricity causes smaller confined concrete region in compression yielding smaller increase in strength of concrete. Accordingly, the ultimate eccentric confined strength is gradually reduced from the fully confined value $f_{cc}$ (at zero eccentricity) to the unconfined value $f^{\prime}_c$ (at infinite eccentricity) as a function of the ratio of compression area to total area of each eccentricity. This approach is used to implement an adaptive Mander model for analyzing eccentrically loaded columns. Generalization of the 3D moment of area approach is implemented based on proportional loading, fiber model and the secant stiffness approach, in an incremental-iterative numerical procedure to achieve the equilibrium path of $P-{\varepsilon}$ and $M-{\varphi}$ response up to failure. This numerical analysis is adapted to assess the confining effect in rectangular columns confined with conventional lateral steel. This analysis is validated against experimental data found in the literature showing good correlation to the partial confinement model while rendering the full confinement treatment unsafe.

• Journal of the Korean Ceramic Society
• /
• v.35 no.1
• /
• pp.55-65
• /
• 1998

The oxidation behavior of Ag-36.8a%Cu-7.4at%Ti alloy brazed on Si3N4 substrate was investigated at 400, 500 and 600$^{\circ}C$ in air. Under this experimental condition Si3N4 and Ag were not oxidized whereas Cu and Ti among the brazing alloy components were oxidizied obeying the parabolic oxidation rate law. The activation energy of oxidation was found to be 80kj/ mol which was smaller than that of pure Cu owing to the presence of oxygen active element of Ti. The outer oxide scale formed from the initial oxidation state was always composed of Cu oxides which were known to be growing by the outward diffusion of Cu ions. As the oxidation progressed the concentration gradient occurred due to the continuous consumption of Cu as Cu oxides and consequently build-up of an Ag-enriched layer below the Cu oxides resulted in the formation of multiple oxide scales composed of Cu oxide (CuO) /Ag-enriched layer/Cu oxide (Cu2O) /Ag-enriched layer. Also the inward diffusing of oxygen through Cu oxide and Ag-enriched layers led to the formation of internal oxides of TiO2.

• Tuberculosis and Respiratory Diseases
• /
• v.83 no.3
• /
• pp.211-217
• /
• 2020

The gold standard method for diagnosis of tuberculosis is the isolation of Mycobacterium tuberculosis through culture, but there is a probability of cross-contamination in simultaneous cultures of samples causing false-positives. This can result in delayed treatment of the underlying disease and drug side effects. In this paper, we reviewed studies on false-positive cultures of M. tuberculosis. Rate of occurrence, effective factors, and extent of false-positives were analyzed. Ways to identify and reduce the false-positives and management of them are critical for all laboratories. In most cases, false-positive is occurring in cases with only one positive culture but negative direct smear. The three most crucial factors in this regard are inappropriate technician function, contamination of reagents, and aerosol production. Thus, to reduce false-positives, good laboratory practice, as well as use of whole-genome sequencing or genotyping of all positive culture samples with a robust, extra pure method and rapid response, are essential for minimizing the rate of false-positives. Indeed, molecular approaches and epidemiological surveillance can provide a valuable tool besides culture to identify possible false positives.

• Journal of the Microelectronics and Packaging Society
• /
• v.6 no.2
• /
• pp.45-49
• /
• 1999

A flammable gas sensor based on the $SnO_2$thin film deposited by the reactive ion assisted deposition was fabricated and ultra-thin Pd layer as catalyst was adsorbed at surface by ion beam sputtering. The initial oxidation states of Pd catalyst were controlled to investigate the role of Pd in the sensing process of inflammale gas sensor through annealing in air and vacuum respectively. The Pd catalyst existing in pure metallic state showed the sensitivity higher than that of PdO. The result might be closely related to the fact that PdO as a surface acceptor would receive electrons via Pd sub-channel from $SnO_2$, and thus which reduces the sensitivity and delay the response time.

• Korean Journal of Materials Research
• /
• v.25 no.10
• /
• pp.566-570
• /
• 2015

$Bi_{0.5}Na_{0.5}TiO_3$ (BNT) based ceramics are considered potential lead-free alternatives for $Pb(Zr,Ti)O_3$(PZT) based ceramics in various applications such as sensors, actuators and transducers. However, BNT-based ceramics have lower electromechanical performance as compared with PZT based ceramics. Therefore, in this work, lead-free bulk $0.99[(Bi_{0.5}Na_{0.5})_{0.935}Ba_{0.065}]_{(1-x)}La_xTiO_3-0.01SrZO_3$ (BNBTLax-SZ, with x = 0, 0.01, 0.02) ceramics were synthesized by a conventional solid state reaction The crystal structure, dielectric response, degree of diffuseness and electric-field-induced strain properties were investigated as a function of different La concentrations. All samples were crystallized into a single phase perovskite structure. The temperature dependent dielectric response of La-modified BNBT-SZ ceramics showed lower dielectric response and improved field-induced strain response. The field induced strain increased from 0.17%_for pure BNBT-SZ to 0.38 % for 1 mol.% La-modified BNBT-SZ ceramics at an applied electric field of 6 kV/mm. These results show that La-modified BNBT-SZ ceramic system is expected to be a new candidate material for lead-free electronic devices.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.21 no.4
• /
• pp.803-814
• /
• 2007

Shenming(神明) exists everywhere in the universe; it affects human beings to feel and contact ideal and peaceful state of Shen(神). Shenming theory(神明思想) in ${\ulcorner}$Hwang Ti Nei Ching${\lrcorner}$ (黃帝內經) was established by ancient Northeastern Asians who were trying to apply paradigm called TianRenHeYi theory(天人合-思想), unifying man and the Great Spirit(絶對精神) of the universe. Based on present, Shenming(神明) is an idea that can estimate will of Shen(神) which has a key to the future; such concept is founded by both human's mind and action that are designed to seek for the uncertain future. Very pure and devoted mind can sympathize with Shen(神) to accept Shenming(神明). Sehnming theory(神明思想) in ${\ulcorner}$Hwang Ti Nei Ching${\lrcorner}$ (黃帝內經) has a basic concept of living balanced life as a human by accepting Shenming(神明), the Spirit of Universe. Thus, it can be summarized into a phrase, 'Shenming(神明) is a process that human conjures his ultimate destiny called the Great Spirit(絶對精神) in himself.' If a man would be guided by Shenming(神明), the Spirit of Universe, he can live peacefully. Therefore, it is essential to study Shenming theory(神明思想) in ${\ulcorner}$Hwang Ti Nei Ching${\lrcorner}$ (黃帝內經) to aid present people's mental health.

• Journal of the Korean Graphic Arts Communication Society
• /
• v.30 no.2
• /
• pp.35-45
• /
• 2012

Need color separation process to appear number of minimum printing plate waterway maximum printing color at printing process. This time, printing plate is separated three primary colors of C(cyan), M(magenta), Y(yellow). Appear all colors of printing such three primary colors. But, three primary color ink appears 100% dark gray that is not clean as chroma is neared color to 0 because is not pure. As well as, the ink area rate that is whole by over print amount increase of three primary is expanded. As a result, influence in secondary printablity set-off growth by inaccurate color reproduction and ink dry badness, trapping efficiency decline etc.. Apply ink saving method that is replaced as K ink in consisted dark color constituent because three primary colors are over print each other adding one more K(black) plate by method to improve these problem. Therefore, can reduce extension of the total ink area rate, and help in correct color appearance control. As well as, eco-friendly printing process attains improving printablity at the same time curtailment of printing expense by reducing requirement of total ink. Usually, there are UCR(under color removal) and GCR(gray component replacement) to ink saving application method. But, the practical use limit is insufficient state to tribe of technological investigation or field application about these method in domestic printing field. Therefore, in this research, ink saving been bringing by one method of eco-friendly printing confirmed that is applicable in usual domestic printing environment. Also, searched result getting in printablity by ink saving application.

• Journal of Pharmaceutical Investigation
• /
• v.34 no.6
• /
• pp.443-452
• /
• 2004

Habit is the description of the outer appearance of a crystal. If the environment of a growing crystal affects its external shape without changing its internal structure, a different habit results. Crystal habit and the internal structure of a drug can affect bulk and physicochemical properties, which range from flowability to chemical stability. A polymorph is a solid crystalline phase of a given compound resulting from the possibility of at least two different arrangements of the molecules of that compound in the solid state. Chemical stability and solubility changes due to polymorphism can have an impact on a drug's bioavailability and its development program. During crystallization from a solution, crystals separating may consist of a pure component or be a molecular compound. Solvates are molecular complexes that have incorporated the crystallizing solvent molecule in their lattice. When the solvent incorporated in the solvate is water, it is called a hydrate. To distinguish solvates from polymorphs, which are not molecular compounds, the term pseudopolymorph is used. Identification of possible hydrate compounds is important since their aqueous solubilities can be significantly less than their anhydrous forms. Conversion of an anhydrous compound to a hydrate within the dosage form may reduce the dissolution rate and extent of drug absorption. An amorphous solid may be treated as a supercooled liquid in which the arrangement of molecules is random. Amorphous solids lack the three-dimensional long-range order found in crystalline solids. Since amorphous forms are usually of higher thermodynamic energy than corresponding crystalline forms, solubilities as well as dissolution rates are generally greater. A study on crystal form includes characterization of (l)crystal habit, (2)polymorphism, (3)pseudopolymorphism, (4)amorphous solid.

• KSBB Journal
• /
• v.6 no.2
• /
• pp.143-146
• /
• 1991

The liquifying $\alpha-amylase$ production from B. subtilis, A. oryzae and B. natto using wheat and rice bran as low cost culture medium was investigated. Among 3 strains, B. natto showed heights productivity of $\alpha-amylase$ in the outer wheat bran medium. And the optimum culture condition is pH 6.8 and $37^{\circ}C$ for the production of $\alpha-amylase$. The $\alpha-amylase$ activity of the crude enzyme and the purified enzyme are 256 unit/ml and 10,700 unit/ml, respectivitly. The $\alpha-amylase$ from B. natto cultrtured in outer wheat bran medium was purified into nearly a pure state(98.7%). And the molecular weight of the purified $\alpha-amylase$ was 34,000.