• Journal of Korean Society for Quality Management
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• v.17 no.2
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• pp.27-35
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• 1989

Software developers often allocate a significant amount of effort to software testing. But for most business-related software system it is natural to expect the continued discovery of defects after the software system is released into field. Such defects are usually very expensive to fix and have the potential to cause great damages to the users. It is important to stop testing the software and release it to the users at the correct time. In this paper, we propose the determination of the optimal number of software test oy minimizing a total expected software cost. A numerical example is used when the criterion is the expected profit. The result indicates that the proposed software release policy based on the number of software test can be a good alternative to the existing policy.

• Archives of Pharmacal Research
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• v.19 no.4
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• pp.280-285
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• 1996

The sustained release dosage form which delivers melatonin (MT) in a circadian fashion over 8 h is of clinical value for those who have disordered circadian rhythms because of its short halflife. The purpose of this study was to evaluate the gelling properties and release characteristics of alginate beads varying multivalent cationic species $(Al^{+++}, \; Ba^{++}, \; Ca^{++}, \; Mg^{++}, \; Fe^{+++}, \; Zn^{++})$. The surface morphologies of Ca- and Ba-alginate beads were also studied using scanning electron microscope (SEM). MT, an indole amide pineal hormone was used as a model drug. The $Ca^{++}, \; Ba^{++}, \; Zn^{++}, \; Al^{++}\; and\; Fe^{+++}\; ions\; except\; Mg^{++}$ induced gelling of sodium alginate. The strength of multivalent cationic alginate beads was as follows: $Al^{+++}\llFe^{+++} the induced hydrogel beads were very fragile and less spherical. Fe-alginate beads were also fragile but stronger compared to Al-alginate beads. Ba-alginate beads had a similar gelling strength but was less spherical when compared to Ca-alginate beads. Zn-alginate beads were weaker than Ca- and Ba-alginate beads. Very crude and rough crystals of Ba- and Ca-alginate beads at higher magnifications were observed. However, the type and shape of rough crystals of Ba- and Ca-alginate beads were quite different. No significant differences in release profiles from MT-loaded multivalent cationic alginate beads were observed in the gastric fluid. Most drugs were continuously released upto 80% for 5 h, mainly governed by the passive diffusion without swelling and disintegrating the alginate beads. In the intestinal fluid, there was a significant difference iq the release profiles of MT-loaded multivalent cationic alginate beads. The release rate of Ca-alginate beads was faster when compared to other multivalent cationic alginate beads and was completed for 3 h. Ba-alginate beads had a very long lag time (7 h) and then rapidly released thereafter. MT was continuously released from Feand Zn-alginate beads with initial burstout release. It is assumed that the different release rofiles of multivalent cationic alginate beads resulted from forces of swelling and disintegration of alginate beads in addition to passive diffusion, depending on types of multivalent ions, gelling strength and drug solubility. It was estimated that 0.2M $CaCl_2$ concentration was optimal in terms of trapping efficiency of MT and gelling strength of Ca-alginate beads. In the gastric fluid, Ca-alginate beads gelled at 0.2 M $CaCl_2$ concentration had higher bead strength, resulting in the most retarded release when compared to other concentrations. In the intestinal fluid, the decreased release of Ca-alginate beads prepared at 0.2 M $CaCl_2$ concentration was also observed. However, release profiles of Ca-alginate beads were quite similar regardless of $CaCl_2$ concentration. Either too low or high $CaCl_2$ concentrations may not be useful for gelling and curing of alginate beads. Optimal $CaCl_2$ concentrations must be decided in terms of trapping efficiency and release and profiles of drug followed by curing time and gelling strength of alginate beads.

• International Journal of Advanced Culture Technology
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• v.8 no.3
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• pp.211-215
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• 2020

Currently, most of the chlorine dioxide gas is processed at the beginning of storage or distribution. It has the disadvantage of not being able to continuously process gas since there is no system that can continuously process it during the distribution process. Therefore, in order to minimize changes in freshness and quality during the distribution process of agrifood, there is a need for a sustained-release chlorine dioxide gas treatment technology that can be continuously released. Therefore, in this study, the film to be used was examined so that the chlorine dioxide gas can be continuously released for a certain period of time, the concentration of the reactant and the viscosity at the time of the reaction were determined, and a chlorine dioxide gas gel pack was manufactured using this optimal condition. In addition, the gel pack was used to measure the amount of chlorine dioxide gas released and the sterilization effect of food poisoning bacteria.

• Water for future
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• v.29 no.1
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• pp.235-248
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• 1996

Apreliminary release scheme (PRS) is suggested for the operating rules during flood period to deal with conflicts between flood control and water conservation purposes. PRS can be used to decide the optimum releases, based on the forecast of an oncoming flood and flow rate at the control point downstream when comparing the variable restricted water level (VRWL) for flood control with the minimum required water level (MRWL) for conservation use. The model is applied to Chungju and Daechung reservoirs through simulations of the technique. This study illustrates the procedure to decide the time and size for preliminary releases. Also, effects of duration and magnitude of preliminary release are reviewed based on historicqal flood records. The simulation results indicate that the proposed PRS is effective for the managers to find optimal operating policies during flood period. The proposed scheme can be used with main release scheme using real-time operation on hour-to-hour basis to decide the release for a flood.

• Journal of the Semiconductor & Display Technology
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• v.22 no.3
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• pp.41-45
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• 2023

Currently, the method of loading items in the warehouse, the worker directly decides the loading location, and the most used method is to load the product at the location closest to the entrance. This can be effective when there is no difference in the required amount for goods, but when there is a difference in the required amount for goods, it is inefficient because items with a small required amount are loaded near the entrance and occupy the corresponding space for a long time. Therefore, in order to minimize the release time of goods, it is essential to select an appropriate location when loading goods. In this study, a method for determining the loading location by predicting the required amount of goods was studied to select the optimal loading location. Deep learning based bidirectional long-term memory networks (Bi-LSTM) was used to predict the required amount for goods. This study compares and analyzes the release time of goods in the conventional method of loading close to the entrance and in the loading method using the required amount for goods using the Bi-LSTM model.

• Journal of the Korean Institute of Gas
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• v.20 no.5
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• pp.104-111
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• 2016

Recently, the quantities of chemical material are increasing in chemical industries. At that time, release accident is increasing due to aging of equipment, mechanical failure, human error, etc. and industrial complexes found community properties in a specific area. For that matter, chemical release accident can lead to hight probability of large disaster. There is a need to analyze the boundaries optimal sensor placement calculated by selecting release scenarios through release condition and wether condition in a chemical process for release detection and response. This paper is to investigate chlorine release accident scenarios using COMSOL. Through accident scenarios, a numerical calculation is studied to determine optimized sensor placement with weight of detection probability, detection time and concentration. In addition, validity of sensor placement is improved by robustness analysis about unpredicted accident scenarios. Therefore, this verifies our studies can be effectively applicable on any process. As mention above, the result of this study can help to place mobile sensor, to track gas release based concentration data.

• International Journal of Reliability and Applications
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• v.2 no.3
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• pp.147-160
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• 2001

The reliability of computer software is of prime importance for all developers of software. The complicated nature of detecting and removing faults from software has led to a plethora of models for reliability growth. One of the most basic of these is the Jelinski Moranda model, where it is assumed that there are N faults in the software, and that in testing, bugs (or faults) are encountered (and removed when defected) according to a stochastic process at a rate which at a given point in time is proportional to the number of bugs remaining in the system. In this research, we consider the possibility that imperfect repair may occur in any attempt to remove a detected bug in the Jelinski Moranda model. We let p represent the probability that a fault which is discovered or detected is actually perfectly repaired. The possibility that the probability p may differ before and after release of the software is also considered. The distribution of both the number of bugs detected and perfectly repaired in a given time period is studied. Cost models for the development and release of software are investigated, and the impact of the parameter p on the optimal release time minimizing expected costs is assessed.

• Journal of Information Processing Systems
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• v.8 no.1
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• pp.21-54
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• 2012

As we know every software development process is pretty large and consists of different modules. This raises the idea of prioritizing different software modules so that important modules can be tested by preference. In the software testing process, it is not possible to test each and every module regressively, which is due to time and cost constraints. To deal with these constraints, this paper proposes an approach that is based on the fuzzy multi-criteria approach for prioritizing several software modules and calculates optimal time and cost for software testing by using fuzzy logic and the fault tolerance approach.

• Archives of Plastic Surgery
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• v.36 no.1
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• pp.19-23
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• 2009

Purpose: Platelet transplantation is a novel therapeutic strategy for acceleration of wound healing. When applying platelets, efficacy of adding thrombin to stimulate growth factor release from platelets has already been proved. However, no quantitative data of the thrombin treatment has been reported. The purpose of this study was to determine the optimal thrombin concentration to maximize growth factor release of platelets. In particular, this study was designed to quantify levels of platelet derived growth factor(PDGF)-BB, which is a major growth factor contained in the platelets, in vitro. Methods: Fresh platelets were obtained from a blood bank. They were suspended in DMEM/F - 12 and incubated with thrombin of various concentrations. The concentrations of thrombin tested were 0, 6.25, 12.5, 25, 50, 100, 200, and 400 IU/ml. After 30 minutes, 1, 3, 5, and 7 days, the levels of PDGF - BB were measured using enzyme linked immunosorbent assay. Platelets from four donors were included in this study. Each sample was tested in triplicate and the mean value was used as a data for each sample. Results: The addition of thrombin increased the level of PDGF - BB. Increases in storage time of platelets resulted in decreased levels of PDGF - BB. Higher levels of PDGF were detected in consort with increased thrombin concentrations. However, there was no significant difference between samples of 200 and 400 IU/ml concentrations. Conclusion: The results indicate that adding thrombin accelerates the release of growth factors from platelets and the optimal thrombin concentration to maximize this function is 200 IU/ml.

• Korean Journal of Applied Biomechanics
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• v.21 no.5
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• pp.653-660
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• 2011

The purpose of this study was to compare selected kinematic variables between male medalists and a Korean male javelin thrower at the IAAF World Championships, Daegu 2011. The three medalists and one Korean javelin thrower that participated in the Championships were videotaped using three high-speed cameras (300 frames/s, EX-F1 Exilim, Casio, Japan). The results showed that the release and attitude angles of the Korean male javelin thrower (KMJT) were greater than that of the medalists, whereas the attack angle of the KMJT was smaller than that of the medalists. This study also found that the KMJT clearly had a lower release height than the medalists. As a possible adaptation of his physique to the skill, the KMJT used a small trunk inclination angle and produced greater inclination angles at his upper extremities. These results may be linked to an increase in the release angle of the KMJT. There were some difference between the KMJT and the medalists in terms of the length and duration of the delivery phase. In harmony with the shorter length of the delivery phase, its duration was shorter for the KMJT in comparison to the medalists. Because the delivery stride is considered to be a primary generator of endpoint speed, this decrease in the delivery phase time would decrease the javelin velocity at release. The amount of time taken in the delivery phase may be a critical factor to enhance a javelin thrower's performance. Thus, rhythmic movement training specifically designed for the KMJT will help him attain an optimal throwing position.